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CWE-476

5,435 CVEs • Abstraction: Base • Likelihood of Exploit: Medium

NULL Pointer Dereference

The product dereferences a pointer that it expects to be valid but is NULL.

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CVEs (5,435)

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1Linux
1Linux Kernel
Jun 17, 2026
Jan 23, 2026
N/A· v4
5.5 MEDIUM· v3
N/A· v2
In the Linux kernel, the following vulnerability has been resolved: idpf: Fix RSS LUT NULL ptr issue after soft reset During soft reset, the RSS LUT is freed and not restored unless the interface is up. If an ethtool c...Show more
In the Linux kernel, the following vulnerability has been resolved: idpf: Fix RSS LUT NULL ptr issue after soft reset During soft reset, the RSS LUT is freed and not restored unless the interface is up. If an ethtool command that accesses the rss lut is attempted immediately after reset, it will result in NULL ptr dereference. Also, there is no need to reset the rss lut if the soft reset does not involve queue count change. After soft reset, set the RSS LUT to default values based on the updated queue count only if the reset was a result of a queue count change and the LUT was not configured by the user. In all other cases, don't touch the LUT. Steps to reproduce: ** Bring the interface down (if up) ifconfig eth1 down ** update the queue count (eg., 27->20) ethtool -L eth1 combined 20 ** display the RSS LUT ethtool -x eth1 [82375.558338] BUG: kernel NULL pointer dereference, address: 0000000000000000 [82375.558373] #PF: supervisor read access in kernel mode [82375.558391] #PF: error_code(0x0000) - not-present page [82375.558408] PGD 0 P4D 0 [82375.558421] Oops: Oops: 0000 [#1] SMP NOPTI <snip> [82375.558516] RIP: 0010:idpf_get_rxfh+0x108/0x150 [idpf] [82375.558786] Call Trace: [82375.558793] <TASK> [82375.558804] rss_prepare.isra.0+0x187/0x2a0 [82375.558827] rss_prepare_data+0x3a/0x50 [82375.558845] ethnl_default_doit+0x13d/0x3e0 [82375.558863] genl_family_rcv_msg_doit+0x11f/0x180 [82375.558886] genl_rcv_msg+0x1ad/0x2b0 [82375.558902] ? __pfx_ethnl_default_doit+0x10/0x10 [82375.558920] ? __pfx_genl_rcv_msg+0x10/0x10 [82375.558937] netlink_rcv_skb+0x58/0x100 [82375.558957] genl_rcv+0x2c/0x50 [82375.558971] netlink_unicast+0x289/0x3e0 [82375.558988] netlink_sendmsg+0x215/0x440 [82375.559005] __sys_sendto+0x234/0x240 [82375.559555] __x64_sys_sendto+0x28/0x30 [82375.560068] x64_sys_call+0x1909/0x1da0 [82375.560576] do_syscall_64+0x7a/0xfa0 [82375.561076] ? clear_bhb_loop+0x60/0xb0 [82375.561567] entry_SYSCALL_64_after_hwframe+0x76/0x7e <snip>Show less
1Linux
1Linux Kernel
Jul 14, 2026
Jan 23, 2026
N/A· v4
5.5 MEDIUM· v3
N/A· v2
In the Linux kernel, the following vulnerability has been resolved: libceph: return the handler error from mon_handle_auth_done() Currently any error from ceph_auth_handle_reply_done() is propagated via finish_auth() b...Show more
In the Linux kernel, the following vulnerability has been resolved: libceph: return the handler error from mon_handle_auth_done() Currently any error from ceph_auth_handle_reply_done() is propagated via finish_auth() but isn't returned from mon_handle_auth_done(). This results in higher layers learning that (despite the monitor considering us to be successfully authenticated) something went wrong in the authentication phase and reacting accordingly, but msgr2 still trying to proceed with establishing the session in the background. In the case of secure mode this can trigger a WARN in setup_crypto() and later lead to a NULL pointer dereference inside of prepare_auth_signature().Show less
1Linux
1Linux Kernel
Jun 17, 2026
Jan 23, 2026
N/A· v4
5.5 MEDIUM· v3
N/A· v2
In the Linux kernel, the following vulnerability has been resolved: libceph: make free_choose_arg_map() resilient to partial allocation free_choose_arg_map() may dereference a NULL pointer if its caller fails after a p...Show more
In the Linux kernel, the following vulnerability has been resolved: libceph: make free_choose_arg_map() resilient to partial allocation free_choose_arg_map() may dereference a NULL pointer if its caller fails after a partial allocation. For example, in decode_choose_args(), if allocation of arg_map->args fails, execution jumps to the fail label and free_choose_arg_map() is called. Since arg_map->size is updated to a non-zero value before memory allocation, free_choose_arg_map() will iterate over arg_map->args and dereference a NULL pointer. To prevent this potential NULL pointer dereference and make free_choose_arg_map() more resilient, add checks for pointers before iterating.Show less
1Linux
1Linux Kernel
Jun 17, 2026
Jan 23, 2026
N/A· v4
5.5 MEDIUM· v3
N/A· v2
In the Linux kernel, the following vulnerability has been resolved: net/sched: act_api: avoid dereferencing ERR_PTR in tcf_idrinfo_destroy syzbot reported a crash in tc_act_in_hw() during netns teardown where tcf_idrin...Show more
In the Linux kernel, the following vulnerability has been resolved: net/sched: act_api: avoid dereferencing ERR_PTR in tcf_idrinfo_destroy syzbot reported a crash in tc_act_in_hw() during netns teardown where tcf_idrinfo_destroy() passed an ERR_PTR(-EBUSY) value as a tc_action pointer, leading to an invalid dereference. Guard against ERR_PTR entries when iterating the action IDR so teardown does not call tc_act_in_hw() on an error pointer.Show less
1Linux
1Linux Kernel
Jun 17, 2026
Jan 23, 2026
N/A· v4
5.5 MEDIUM· v3
N/A· v2
In the Linux kernel, the following vulnerability has been resolved: idpf: Fix RSS LUT NULL pointer crash on early ethtool operations The RSS LUT is not initialized until the interface comes up, causing the following NU...Show more
In the Linux kernel, the following vulnerability has been resolved: idpf: Fix RSS LUT NULL pointer crash on early ethtool operations The RSS LUT is not initialized until the interface comes up, causing the following NULL pointer crash when ethtool operations like rxhash on/off are performed before the interface is brought up for the first time. Move RSS LUT initialization from ndo_open to vport creation to ensure LUT is always available. This enables RSS configuration via ethtool before bringing the interface up. Simplify LUT management by maintaining all changes in the driver's soft copy and programming zeros to the indirection table when rxhash is disabled. Defer HW programming until the interface comes up if it is down during rxhash and LUT configuration changes. Steps to reproduce: ** Load idpf driver; interfaces will be created modprobe idpf ** Before bringing the interfaces up, turn rxhash off ethtool -K eth2 rxhash off [89408.371875] BUG: kernel NULL pointer dereference, address: 0000000000000000 [89408.371908] #PF: supervisor read access in kernel mode [89408.371924] #PF: error_code(0x0000) - not-present page [89408.371940] PGD 0 P4D 0 [89408.371953] Oops: Oops: 0000 [#1] SMP NOPTI <snip> [89408.372052] RIP: 0010:memcpy_orig+0x16/0x130 [89408.372310] Call Trace: [89408.372317] <TASK> [89408.372326] ? idpf_set_features+0xfc/0x180 [idpf] [89408.372363] __netdev_update_features+0x295/0xde0 [89408.372384] ethnl_set_features+0x15e/0x460 [89408.372406] genl_family_rcv_msg_doit+0x11f/0x180 [89408.372429] genl_rcv_msg+0x1ad/0x2b0 [89408.372446] ? __pfx_ethnl_set_features+0x10/0x10 [89408.372465] ? __pfx_genl_rcv_msg+0x10/0x10 [89408.372482] netlink_rcv_skb+0x58/0x100 [89408.372502] genl_rcv+0x2c/0x50 [89408.372516] netlink_unicast+0x289/0x3e0 [89408.372533] netlink_sendmsg+0x215/0x440 [89408.372551] __sys_sendto+0x234/0x240 [89408.372571] __x64_sys_sendto+0x28/0x30 [89408.372585] x64_sys_call+0x1909/0x1da0 [89408.372604] do_syscall_64+0x7a/0xfa0 [89408.373140] ? clear_bhb_loop+0x60/0xb0 [89408.373647] entry_SYSCALL_64_after_hwframe+0x76/0x7e [89408.378887] </TASK> <snip>Show less
1Linux
1Linux Kernel
Jun 17, 2026
Jan 23, 2026
N/A· v4
5.5 MEDIUM· v3
N/A· v2
In the Linux kernel, the following vulnerability has been resolved: net: do not write to msg_get_inq in callee NULL pointer dereference fix. msg_get_inq is an input field from caller to callee. Don't set it in the cal...Show more
In the Linux kernel, the following vulnerability has been resolved: net: do not write to msg_get_inq in callee NULL pointer dereference fix. msg_get_inq is an input field from caller to callee. Don't set it in the callee, as the caller may not clear it on struct reuse. This is a kernel-internal variant of msghdr only, and the only user does reinitialize the field. So this is not critical for that reason. But it is more robust to avoid the write, and slightly simpler code. And it fixes a bug, see below. Callers set msg_get_inq to request the input queue length to be returned in msg_inq. This is equivalent to but independent from the SO_INQ request to return that same info as a cmsg (tp->recvmsg_inq). To reduce branching in the hot path the second also sets the msg_inq. That is WAI. This is a fix to commit 4d1442979e4a ("af_unix: don't post cmsg for SO_INQ unless explicitly asked for"), which fixed the inverse. Also avoid NULL pointer dereference in unix_stream_read_generic if state->msg is NULL and msg->msg_get_inq is written. A NULL state->msg can happen when splicing as of commit 2b514574f7e8 ("net: af_unix: implement splice for stream af_unix sockets"). Also collapse two branches using a bitwise or.Show less
1Linux
1Linux Kernel
Jul 14, 2026
Jan 23, 2026
N/A· v4
5.5 MEDIUM· v3
N/A· v2
In the Linux kernel, the following vulnerability has been resolved: net: mscc: ocelot: Fix crash when adding interface under a lag Commit 15faa1f67ab4 ("lan966x: Fix crash when adding interface under a lag") fixed a si...Show more
In the Linux kernel, the following vulnerability has been resolved: net: mscc: ocelot: Fix crash when adding interface under a lag Commit 15faa1f67ab4 ("lan966x: Fix crash when adding interface under a lag") fixed a similar issue in the lan966x driver caused by a NULL pointer dereference. The ocelot_set_aggr_pgids() function in the ocelot driver has similar logic and is susceptible to the same crash. This issue specifically affects the ocelot_vsc7514.c frontend, which leaves unused ports as NULL pointers. The felix_vsc9959.c frontend is unaffected as it uses the DSA framework which registers all ports. Fix this by checking if the port pointer is valid before accessing it.Show less
1Linux
1Linux Kernel
Jun 17, 2026
Jan 23, 2026
N/A· v4
5.5 MEDIUM· v3
N/A· v2
In the Linux kernel, the following vulnerability has been resolved: idpf: detach and close netdevs while handling a reset Protect the reset path from callbacks by setting the netdevs to detached state and close any net...Show more
In the Linux kernel, the following vulnerability has been resolved: idpf: detach and close netdevs while handling a reset Protect the reset path from callbacks by setting the netdevs to detached state and close any netdevs in UP state until the reset handling has completed. During a reset, the driver will de-allocate resources for the vport, and there is no guarantee that those will recover, which is why the existing vport_ctrl_lock does not provide sufficient protection. idpf_detach_and_close() is called right before reset handling. If the reset handling succeeds, the netdevs state is recovered via call to idpf_attach_and_open(). If the reset handling fails the netdevs remain down. The detach/down calls are protected with RTNL lock to avoid racing with callbacks. On the recovery side the attach can be done without holding the RTNL lock as there are no callbacks expected at that point, due to detach/close always being done first in that flow. The previous logic restoring the netdevs state based on the IDPF_VPORT_UP_REQUESTED flag in the init task is not needed anymore, hence the removal of idpf_set_vport_state(). The IDPF_VPORT_UP_REQUESTED is still being used to restore the state of the netdevs following the reset, but has no use outside of the reset handling flow. idpf_init_hard_reset() is converted to void, since it was used as such and there is no error handling being done based on its return value. Before this change, invoking hard and soft resets simultaneously will cause the driver to lose the vport state: ip -br a <inf> UP echo 1 > /sys/class/net/ens801f0/device/reset& \ ethtool -L ens801f0 combined 8 ip -br a <inf> DOWN ip link set <inf> up ip -br a <inf> DOWN Also in case of a failure in the reset path, the netdev is left exposed to external callbacks, while vport resources are not initialized, leading to a crash on subsequent ifup/down: [408471.398966] idpf 0000:83:00.0: HW reset detected [408471.411744] idpf 0000:83:00.0: Device HW Reset initiated [408472.277901] idpf 0000:83:00.0: The driver was unable to contact the device's firmware. Check that the FW is running. Driver state= 0x2 [408508.125551] BUG: kernel NULL pointer dereference, address: 0000000000000078 [408508.126112] #PF: supervisor read access in kernel mode [408508.126687] #PF: error_code(0x0000) - not-present page [408508.127256] PGD 2aae2f067 P4D 0 [408508.127824] Oops: Oops: 0000 [#1] SMP NOPTI ... [408508.130871] RIP: 0010:idpf_stop+0x39/0x70 [idpf] ... [408508.139193] Call Trace: [408508.139637] <TASK> [408508.140077] __dev_close_many+0xbb/0x260 [408508.140533] __dev_change_flags+0x1cf/0x280 [408508.140987] netif_change_flags+0x26/0x70 [408508.141434] dev_change_flags+0x3d/0xb0 [408508.141878] devinet_ioctl+0x460/0x890 [408508.142321] inet_ioctl+0x18e/0x1d0 [408508.142762] ? _copy_to_user+0x22/0x70 [408508.143207] sock_do_ioctl+0x3d/0xe0 [408508.143652] sock_ioctl+0x10e/0x330 [408508.144091] ? find_held_lock+0x2b/0x80 [408508.144537] __x64_sys_ioctl+0x96/0xe0 [408508.144979] do_syscall_64+0x79/0x3d0 [408508.145415] entry_SYSCALL_64_after_hwframe+0x76/0x7e [408508.145860] RIP: 0033:0x7f3e0bb4caffShow less
1Free5gc
1Pcf
Jun 17, 2026
Jan 23, 2026
N/A· v4
7.5 HIGH· v3
N/A· v2
Null pointer dereference in free5gc pcf 1.4.0 in file internal/sbi/processor/ampolicy.go in function HandleDeletePoliciesPolAssoId.
1Libexpat Project
1Libexpat
Jun 17, 2026
Jan 23, 2026
N/A· v4
2.5 LOW· v3
N/A· v2
In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data.
-
-
Jun 17, 2026
Jan 23, 2026
N/A· v4
8.4 HIGH· v3
N/A· v2
A flaw was found in SIPp. A remote attacker could exploit this by sending specially crafted Session Initiation Protocol (SIP) messages during an active call. This vulnerability, a NULL pointer dereference, can cause the...Show more
A flaw was found in SIPp. A remote attacker could exploit this by sending specially crafted Session Initiation Protocol (SIP) messages during an active call. This vulnerability, a NULL pointer dereference, can cause the application to crash, leading to a denial of service. Under specific conditions, it may also allow an attacker to execute unauthorized code, compromising the system's integrity and availability.Show less
1Linuxfoundation
1Rekor
Jun 17, 2026
Jan 22, 2026
N/A· v4
5.3 MEDIUM· v3
N/A· v2
Rekor is a software supply chain transparency log. In versions 1.4.3 and below, the entry implementation can panic on attacker-controlled input when canonicalizing a proposed entry with an empty spec.message, causing nil...Show more
Rekor is a software supply chain transparency log. In versions 1.4.3 and below, the entry implementation can panic on attacker-controlled input when canonicalizing a proposed entry with an empty spec.message, causing nil Pointer Dereference. Function validate() returns nil (success) when message is empty, leaving sign1Msg uninitialized, and Canonicalize() later dereferences v.sign1Msg.Payload. A malformed proposed entry of the cose/v0.0.1 type can cause a panic on a thread within the Rekor process. The thread is recovered so the client receives a 500 error message and service still continues, so the availability impact of this is minimal. This issue has been fixed in version 1.5.0.Show less
2Dlemstra
Imagemagick
2Imagemagick
Magick.net
Jun 17, 2026
Jan 22, 2026
N/A· v4
7.5 HIGH· v3
N/A· v2
ImageMagick is free and open-source software used for editing and manipulating digital images. Versions 14.10.1 and below have a NULL pointer dereference vulnerability in the MSL (Magick Scripting Language) parser when p...Show more
ImageMagick is free and open-source software used for editing and manipulating digital images. Versions 14.10.1 and below have a NULL pointer dereference vulnerability in the MSL (Magick Scripting Language) parser when processing <comment> tags before images are loaded. This can lead to DoS attack due to assertion failure (debug builds) or NULL pointer dereference (release builds). This issue is fixed in version 14.10.2.Show less
1Linuxfoundation
1Everest
Jun 17, 2026
Jan 21, 2026
N/A· v4
7.4 HIGH· v3
N/A· v2
EVerest is an EV charging software stack. Prior to version 2025.10.0, during the deserialization of a `DC_ChargeLoopRes` message that includes Receipt as well as TaxCosts, the vector `<DetailedTax>tax_costs` in the targe...Show more
EVerest is an EV charging software stack. Prior to version 2025.10.0, during the deserialization of a `DC_ChargeLoopRes` message that includes Receipt as well as TaxCosts, the vector `<DetailedTax>tax_costs` in the target `Receipt` structure is accessed out of bounds. This occurs in the method `template <> void convert(const struct iso20_dc_DetailedTaxType& in, datatypes::DetailedTax& out)` which leads to a null pointer dereference and causes the module to terminate. The EVerest processes and all its modules shut down, affecting all EVSE. Version 2025.10.0 fixes the issue.Show less
1Linux
1Linux Kernel
Jul 14, 2026
Jan 21, 2026
N/A· v4
5.5 MEDIUM· v3
N/A· v2
In the Linux kernel, the following vulnerability has been resolved: net: sock: fix hardened usercopy panic in sock_recv_errqueue skbuff_fclone_cache was created without defining a usercopy region, [1] unlike skbuff_hea...Show more
In the Linux kernel, the following vulnerability has been resolved: net: sock: fix hardened usercopy panic in sock_recv_errqueue skbuff_fclone_cache was created without defining a usercopy region, [1] unlike skbuff_head_cache which properly whitelists the cb[] field. [2] This causes a usercopy BUG() when CONFIG_HARDENED_USERCOPY is enabled and the kernel attempts to copy sk_buff.cb data to userspace via sock_recv_errqueue() -> put_cmsg(). The crash occurs when: 1. TCP allocates an skb using alloc_skb_fclone() (from skbuff_fclone_cache) [1] 2. The skb is cloned via skb_clone() using the pre-allocated fclone [3] 3. The cloned skb is queued to sk_error_queue for timestamp reporting 4. Userspace reads the error queue via recvmsg(MSG_ERRQUEUE) 5. sock_recv_errqueue() calls put_cmsg() to copy serr->ee from skb->cb [4] 6. __check_heap_object() fails because skbuff_fclone_cache has no usercopy whitelist [5] When cloned skbs allocated from skbuff_fclone_cache are used in the socket error queue, accessing the sock_exterr_skb structure in skb->cb via put_cmsg() triggers a usercopy hardening violation: [ 5.379589] usercopy: Kernel memory exposure attempt detected from SLUB object 'skbuff_fclone_cache' (offset 296, size 16)! [ 5.382796] kernel BUG at mm/usercopy.c:102! [ 5.383923] Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI [ 5.384903] CPU: 1 UID: 0 PID: 138 Comm: poc_put_cmsg Not tainted 6.12.57 #7 [ 5.384903] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 5.384903] RIP: 0010:usercopy_abort+0x6c/0x80 [ 5.384903] Code: 1a 86 51 48 c7 c2 40 15 1a 86 41 52 48 c7 c7 c0 15 1a 86 48 0f 45 d6 48 c7 c6 80 15 1a 86 48 89 c1 49 0f 45 f3 e8 84 27 88 ff <0f> 0b 490 [ 5.384903] RSP: 0018:ffffc900006f77a8 EFLAGS: 00010246 [ 5.384903] RAX: 000000000000006f RBX: ffff88800f0ad2a8 RCX: 1ffffffff0f72e74 [ 5.384903] RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff87b973a0 [ 5.384903] RBP: 0000000000000010 R08: 0000000000000000 R09: fffffbfff0f72e74 [ 5.384903] R10: 0000000000000003 R11: 79706f6372657375 R12: 0000000000000001 [ 5.384903] R13: ffff88800f0ad2b8 R14: ffffea00003c2b40 R15: ffffea00003c2b00 [ 5.384903] FS: 0000000011bc4380(0000) GS:ffff8880bf100000(0000) knlGS:0000000000000000 [ 5.384903] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 5.384903] CR2: 000056aa3b8e5fe4 CR3: 000000000ea26004 CR4: 0000000000770ef0 [ 5.384903] PKRU: 55555554 [ 5.384903] Call Trace: [ 5.384903] <TASK> [ 5.384903] __check_heap_object+0x9a/0xd0 [ 5.384903] __check_object_size+0x46c/0x690 [ 5.384903] put_cmsg+0x129/0x5e0 [ 5.384903] sock_recv_errqueue+0x22f/0x380 [ 5.384903] tls_sw_recvmsg+0x7ed/0x1960 [ 5.384903] ? srso_alias_return_thunk+0x5/0xfbef5 [ 5.384903] ? schedule+0x6d/0x270 [ 5.384903] ? srso_alias_return_thunk+0x5/0xfbef5 [ 5.384903] ? mutex_unlock+0x81/0xd0 [ 5.384903] ? __pfx_mutex_unlock+0x10/0x10 [ 5.384903] ? __pfx_tls_sw_recvmsg+0x10/0x10 [ 5.384903] ? _raw_spin_lock_irqsave+0x8f/0xf0 [ 5.384903] ? _raw_read_unlock_irqrestore+0x20/0x40 [ 5.384903] ? srso_alias_return_thunk+0x5/0xfbef5 The crash offset 296 corresponds to skb2->cb within skbuff_fclones: - sizeof(struct sk_buff) = 232 - offsetof(struct sk_buff, cb) = 40 - offset of skb2.cb in fclones = 232 + 40 = 272 - crash offset 296 = 272 + 24 (inside sock_exterr_skb.ee) This patch uses a local stack variable as a bounce buffer to avoid the hardened usercopy check failure. [1] https://elixir.bootlin.com/linux/v6.12.62/source/net/ipv4/tcp.c#L885 [2] https://elixir.bootlin.com/linux/v6.12.62/source/net/core/skbuff.c#L5104 [3] https://elixir.bootlin.com/linux/v6.12.62/source/net/core/skbuff.c#L5566 [4] https://elixir.bootlin.com/linux/v6.12.62/source/net/core/skbuff.c#L5491 [5] https://elixir.bootlin.com/linux/v6.12.62/source/mm/slub.c#L5719Show less
1Linux
1Linux Kernel
Jun 17, 2026
Jan 21, 2026
N/A· v4
5.5 MEDIUM· v3
N/A· v2
In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_qfq: Fix NULL deref when deactivating inactive aggregate in qfq_reset `qfq_class->leaf_qdisc->q.qlen > 0` does not imply that the class...Show more
In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_qfq: Fix NULL deref when deactivating inactive aggregate in qfq_reset `qfq_class->leaf_qdisc->q.qlen > 0` does not imply that the class itself is active. Two qfq_class objects may point to the same leaf_qdisc. This happens when: 1. one QFQ qdisc is attached to the dev as the root qdisc, and 2. another QFQ qdisc is temporarily referenced (e.g., via qdisc_get() / qdisc_put()) and is pending to be destroyed, as in function tc_new_tfilter. When packets are enqueued through the root QFQ qdisc, the shared leaf_qdisc->q.qlen increases. At the same time, the second QFQ qdisc triggers qdisc_put and qdisc_destroy: the qdisc enters qfq_reset() with its own q->q.qlen == 0, but its class's leaf qdisc->q.qlen > 0. Therefore, the qfq_reset would wrongly deactivate an inactive aggregate and trigger a null-deref in qfq_deactivate_agg: [ 0.903172] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 0.903571] #PF: supervisor write access in kernel mode [ 0.903860] #PF: error_code(0x0002) - not-present page [ 0.904177] PGD 10299b067 P4D 10299b067 PUD 10299c067 PMD 0 [ 0.904502] Oops: Oops: 0002 [#1] SMP NOPTI [ 0.904737] CPU: 0 UID: 0 PID: 135 Comm: exploit Not tainted 6.19.0-rc3+ #2 NONE [ 0.905157] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.17.0-0-gb52ca86e094d-prebuilt.qemu.org 04/01/2014 [ 0.905754] RIP: 0010:qfq_deactivate_agg (include/linux/list.h:992 (discriminator 2) include/linux/list.h:1006 (discriminator 2) net/sched/sch_qfq.c:1367 (discriminator 2) net/sched/sch_qfq.c:1393 (discriminator 2)) [ 0.906046] Code: 0f 84 4d 01 00 00 48 89 70 18 8b 4b 10 48 c7 c2 ff ff ff ff 48 8b 78 08 48 d3 e2 48 21 f2 48 2b 13 48 8b 30 48 d3 ea 8b 4b 18 0 Code starting with the faulting instruction =========================================== 0: 0f 84 4d 01 00 00 je 0x153 6: 48 89 70 18 mov %rsi,0x18(%rax) a: 8b 4b 10 mov 0x10(%rbx),%ecx d: 48 c7 c2 ff ff ff ff mov $0xffffffffffffffff,%rdx 14: 48 8b 78 08 mov 0x8(%rax),%rdi 18: 48 d3 e2 shl %cl,%rdx 1b: 48 21 f2 and %rsi,%rdx 1e: 48 2b 13 sub (%rbx),%rdx 21: 48 8b 30 mov (%rax),%rsi 24: 48 d3 ea shr %cl,%rdx 27: 8b 4b 18 mov 0x18(%rbx),%ecx ... [ 0.907095] RSP: 0018:ffffc900004a39a0 EFLAGS: 00010246 [ 0.907368] RAX: ffff8881043a0880 RBX: ffff888102953340 RCX: 0000000000000000 [ 0.907723] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 0.908100] RBP: ffff888102952180 R08: 0000000000000000 R09: 0000000000000000 [ 0.908451] R10: ffff8881043a0000 R11: 0000000000000000 R12: ffff888102952000 [ 0.908804] R13: ffff888102952180 R14: ffff8881043a0ad8 R15: ffff8881043a0880 [ 0.909179] FS: 000000002a1a0380(0000) GS:ffff888196d8d000(0000) knlGS:0000000000000000 [ 0.909572] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 0.909857] CR2: 0000000000000000 CR3: 0000000102993002 CR4: 0000000000772ef0 [ 0.910247] PKRU: 55555554 [ 0.910391] Call Trace: [ 0.910527] <TASK> [ 0.910638] qfq_reset_qdisc (net/sched/sch_qfq.c:357 net/sched/sch_qfq.c:1485) [ 0.910826] qdisc_reset (include/linux/skbuff.h:2195 include/linux/skbuff.h:2501 include/linux/skbuff.h:3424 include/linux/skbuff.h:3430 net/sched/sch_generic.c:1036) [ 0.911040] __qdisc_destroy (net/sched/sch_generic.c:1076) [ 0.911236] tc_new_tfilter (net/sched/cls_api.c:2447) [ 0.911447] rtnetlink_rcv_msg (net/core/rtnetlink.c:6958) [ 0.911663] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6861) [ 0.911894] netlink_rcv_skb (net/netlink/af_netlink.c:2550) [ 0.912100] netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344) [ 0.912296] ? __alloc_skb (net/core/skbuff.c:706) [ 0.912484] netlink_sendmsg (net/netlink/af ---truncated---Show less
2Owntone
Owntone Project
2Owntone
Owntone Server
Jun 17, 2026
Jan 20, 2026
N/A· v4
7.5 HIGH· v3
N/A· v2
A NULL pointer dereference in the dacp_reply_playqueueedit_move function (src/httpd_dacp.c) of owntone-server commit b7e385f allows attackers to cause a Denial of Service (DoS) via sending a crafted DACP request to the s...Show more
A NULL pointer dereference in the dacp_reply_playqueueedit_move function (src/httpd_dacp.c) of owntone-server commit b7e385f allows attackers to cause a Denial of Service (DoS) via sending a crafted DACP request to the server.Show less
2Owntone
Owntone Project
2Owntone
Owntone Server
Jun 17, 2026
Jan 20, 2026
N/A· v4
7.5 HIGH· v3
N/A· v2
A NULL pointer dereference in the parse_meta function (src/httpd_daap.c) of owntone-server commit 334beb allows attackers to cause a Denial of Service (DoS) via sending a crafted DAAP request to the server.
2Owntone
Owntone Project
2Owntone
Owntone Server
Jun 17, 2026
Jan 20, 2026
N/A· v4
7.5 HIGH· v3
N/A· v2
NULL pointer dereference in the dacp_reply_playqueueedit_clear function in src/httpd_dacp.c in owntone-server through commit 6d604a1 (newer commit after version 28.12) allows remote attackers to cause a Denial of Service...Show more
NULL pointer dereference in the dacp_reply_playqueueedit_clear function in src/httpd_dacp.c in owntone-server through commit 6d604a1 (newer commit after version 28.12) allows remote attackers to cause a Denial of Service (crash).Show less
2Owntone
Owntone Project
2Owntone
Owntone Server
Jun 17, 2026
Jan 20, 2026
N/A· v4
7.5 HIGH· v3
N/A· v2
NULL pointer dereference in the daap_reply_groups function in src/httpd_daap.c in owntone-server through commit 5e6f19a (newer commit after version 28.2) allows remote attackers to cause a Denial of Service.