Time-of-check Time-of-use (TOCTOU) Race Condition

Akamai Guardicore Platform Agent (GPA) and Zero Trust Client on Linux and macOS allow TOCTOU-based local privilege escalation. The GPA service creates an IPC socket in the world-writable /tmp directory. It accepts unauthenticated IPC control messages. This enables a TOCTOU vulnerability in the HandleSaveLogs() function of the GPA service, by creating a log file and manipulating it into a symlink that points to the targeted path; this can allow an unprivileged local user to make arbitrary root-owned files world-writable. In addition, a diagnostic collection tool (gimmelogs) running with root privileges was vulnerable to command injection from the dbstore, offering a second privilege escalation vector. (On Windows, gimmelogs does not have command injection but does allow writing a ZIP archive to an unintended location.) This affects Akamai Guardicore Platform Agent 7.0 through 7.3.1 and Akamai Zero Trust Client 6.0 through 6.1.5.Show less

In the Linux kernel, the following vulnerability has been resolved: rust_binder: avoid reading the written value in offsets array When sending a transaction, its offsets array is first copied into the target proc's vma, and then the values are read back from there. This is normally fine because the vma is a read-only mapping, so the target process cannot change the value under us. However, if the target process somehow gains the ability to write to its own vma, it could change the offset before it's read back, causing the kernel to misinterpret what the sender meant. If the sender happens to send a payload with a specific shape, this could in the worst case lead to the receiver being able to privilege escalate into the sender. The intent is that gaining the ability to change the read-only vma of your own process should not be exploitable, so remove this TOCTOU read even though it's unexploitable without another Binder bug.Show less

In the Linux kernel, the following vulnerability has been resolved: ceph: fix i_nlink underrun during async unlink During async unlink, we drop the `i_nlink` counter before we receive the completion (that will eventually update the `i_nlink`) because "we assume that the unlink will succeed". That is not a bad idea, but it races against deletions by other clients (or against the completion of our own unlink) and can lead to an underrun which emits a WARNING like this one: WARNING: CPU: 85 PID: 25093 at fs/inode.c:407 drop_nlink+0x50/0x68 Modules linked in: CPU: 85 UID: 3221252029 PID: 25093 Comm: php-cgi8.1 Not tainted 6.14.11-cm4all1-ampere #655 Hardware name: Supermicro ARS-110M-NR/R12SPD-A, BIOS 1.1b 10/17/2023 pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : drop_nlink+0x50/0x68 lr : ceph_unlink+0x6c4/0x720 sp : ffff80012173bc90 x29: ffff80012173bc90 x28: ffff086d0a45aaf8 x27: ffff0871d0eb5680 x26: ffff087f2a64a718 x25: 0000020000000180 x24: 0000000061c88647 x23: 0000000000000002 x22: ffff07ff9236d800 x21: 0000000000001203 x20: ffff07ff9237b000 x19: ffff088b8296afc0 x18: 00000000f3c93365 x17: 0000000000070000 x16: ffff08faffcbdfe8 x15: ffff08faffcbdfec x14: 0000000000000000 x13: 45445f65645f3037 x12: 34385f6369706f74 x11: 0000a2653104bb20 x10: ffffd85f26d73290 x9 : ffffd85f25664f94 x8 : 00000000000000c0 x7 : 0000000000000000 x6 : 0000000000000002 x5 : 0000000000000081 x4 : 0000000000000481 x3 : 0000000000000000 x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff08727d3f91e8 Call trace: drop_nlink+0x50/0x68 (P) vfs_unlink+0xb0/0x2e8 do_unlinkat+0x204/0x288 __arm64_sys_unlinkat+0x3c/0x80 invoke_syscall.constprop.0+0x54/0xe8 do_el0_svc+0xa4/0xc8 el0_svc+0x18/0x58 el0t_64_sync_handler+0x104/0x130 el0t_64_sync+0x154/0x158 In ceph_unlink(), a call to ceph_mdsc_submit_request() submits the CEPH_MDS_OP_UNLINK to the MDS, but does not wait for completion. Meanwhile, between this call and the following drop_nlink() call, a worker thread may process a CEPH_CAP_OP_IMPORT, CEPH_CAP_OP_GRANT or just a CEPH_MSG_CLIENT_REPLY (the latter of which could be our own completion). These will lead to a set_nlink() call, updating the `i_nlink` counter to the value received from the MDS. If that new `i_nlink` value happens to be zero, it is illegal to decrement it further. But that is exactly what ceph_unlink() will do then. The WARNING can be reproduced this way: 1. Force async unlink; only the async code path is affected. Having no real clue about Ceph internals, I was unable to find out why the MDS wouldn't give me the "Fxr" capabilities, so I patched get_caps_for_async_unlink() to always succeed. (Note that the WARNING dump above was found on an unpatched kernel, without this kludge - this is not a theoretical bug.) 2. Add a sleep call after ceph_mdsc_submit_request() so the unlink completion gets handled by a worker thread before drop_nlink() is called. This guarantees that the `i_nlink` is already zero before drop_nlink() runs. The solution is to skip the counter decrement when it is already zero, but doing so without a lock is still racy (TOCTOU). Since ceph_fill_inode() and handle_cap_grant() both hold the `ceph_inode_info.i_ceph_lock` spinlock while set_nlink() runs, this seems like the proper lock to protect the `i_nlink` updates. I found prior art in NFS and SMB (using `inode.i_lock`) and AFS (using `afs_vnode.cb_lock`). All three have the zero check as well.Show less

Due to multiple time-of-check time-of-use race conditions in the resource count check and increment logic, as well as missing validations, users of the platform are able to exceed the allocation limits configured for their accounts/domains. This can be used by an attacker to degrade the infrastructure's resources and lead to denial of service conditions. Users are recommended to upgrade to Apache CloudStack versions 4.20.3.0 or 4.22.0.1, or later, which fixes this issue.Show less

The socket connection handler in aswArPot.sys in the Avast and AVG Windows Anti Rootkit driver before 22.1 allows local attackers to execute arbitrary code in kernel mode or cause a denial of service (memory corruption and OS crash) due to a double fetch vulnerability at aswArPot+0xc4a3.Show less

The base directory (`spring.cloud.config.server.git.basedir`) used by the Spring Cloud Config Server to clone Git repositories to is susceptible to time-of-check-time-of-use (TOCTOU) attacks. Spring Cloud Config 3.1.x: affected from 3.1.0 through 3.1.13 (inclusive); upgrade to 3.1.14 or greater (Enterprise Support Only). Spring Cloud Config 4.1.x: affected from 4.1.0 through 4.1.9 (inclusive); upgrade to 4.1.10 or greater (Enterprise Support Only). Spring Cloud Config 4.2.x: affected from 4.2.0 through 4.2.6 (inclusive); upgrade to 4.2.7 or greater (Enterprise Support Only). Spring Cloud Config 4.3.x: affected from 4.3.0 through 4.3.2 (inclusive); upgrade to 4.3.3 or greater. Spring Cloud Config 5.0.x: affected from 5.0.0 through 5.0.2 (inclusive); upgrade to 5.0.3 or greater.Show less

OpenClaw before 2026.4.22 contains a time-of-check/time-of-use race condition in the OpenShell filesystem bridge that allows attackers to read files outside the intended mount root. Attackers can exploit symlink swaps during filesystem operations to bypass sandbox restrictions and access unauthorized file contents.Show less

OpenClaw before 2026.4.22 contains a time-of-check/time-of-use race condition in OpenShell sandbox filesystem writes that allows attackers to redirect writes outside the intended mount root. Attackers can exploit symlink swaps during filesystem operations to bypass sandbox restrictions and write files outside the local mount root.Show less

OpenClaw before 2026.4.10 contains a server-side request forgery vulnerability in browser navigation policy that allows attackers to bypass hostname validation through DNS rebinding attacks. Attackers can exploit inconsistent hostname resolution between validation and actual network requests to pivot to internal resources via unallowlisted hostname URLs.Show less

Sandboxie-Plus is an open source sandbox-based isolation software for Windows. In versions 1.17.2 and earlier, a Time-of-Check-to-Time-of-Use (TOCTOU) race condition exists during addon installation. When a user installs an addon through the SandMan interface, UpdUtil.exe is spawned as SYSTEM by SbieSvc but stages files in the user-writable %TEMP%\sandboxie-updater directory. After UpdUtil verifies file hashes against the signed addon manifest, install.bat extracts files.cab and executes config.exe from its contents. Between hash verification and extraction, an unprivileged user can replace files.cab with a crafted cabinet containing a malicious executable, which is then run as SYSTEM. No UAC prompt is required. This issue has been fixed in version 1.17.3.Show less

A vulnerability has been found in chatchat-space Langchain-Chatchat up to 0.3.1.3. Impacted is the function files of the file libs/chatchat-server/chatchat/server/api_server/openai_routes.py of the component OpenAI-Compatible File Upload API. Such manipulation of the argument file.filename leads to time-of-check time-of-use. Access to the local network is required for this attack to succeed. The attack requires a high level of complexity. The exploitability is considered difficult. The exploit has been disclosed to the public and may be used. The project was informed of the problem early through an issue report but has not responded yet.Show less

OpenClaw before 2026.4.10 contains a time-of-check-time-of-use vulnerability in the validateScriptFileForShellBleed function that allows local attackers to bypass workspace boundary checks. An attacker with workspace write access can race-condition swap the target file between validation and preflight read, causing the validator to inspect a different file identity than the one that passed the initial boundary check.Show less

A race condition exists in PaperCut MF when processing badge-swipe data from certain HP multifunction devices. Under specific network conditions involving dropped packets and out-of-order sequence counters, the server may incorrectly process fragmented data chunks. If a sequence reset notification fails to reach the server, the server may reject the initial data chunk while erroneously accepting subsequent chunks before a connection reset completes. This leads to the registration of a truncated badge ID string. While this typically results in an authentication failure, the vulnerability is compounded in environments utilizing custom badge-ID post-processing scripts. In such configurations, the truncated string may be transformed into a valid ID belonging to a different user, leading to unauthorized session establishment (Incorrect User Login) on the device.Show less

Improper privilege management in the log rotation mechanism of the Skylight Workspace Config Service in Amazon WorkSpaces for Windows before 2.6.2034.0 allows a local non-admin authenticated user to place arbitrary files into arbitrary locations bypassing file system permission protections, leading to local privilege escalation to SYSTEM.Show less

A vulnerability has been found in PrefectHQ prefect up to 3.6.28.dev1. Affected by this vulnerability is the function validate_restricted_url of the component Webhook/Notification. The manipulation leads to time-of-check time-of-use. It is possible to initiate the attack remotely. The attack is considered to have high complexity. The exploitation appears to be difficult. The exploit has been disclosed to the public and may be used. Upgrading to version 3.6.28.dev2 addresses this issue. The identifier of the patch is 7c70ac54a5e101431d83b9f2681ec88d5e0021ed. Upgrading the affected component is advised. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.Show less

AGL app-framework-main thru 17.1.12 contains a Zip Slip path traversal vulnerability (CWE-22) combined with a TOCTOU race condition (CWE-367) in the widget installation flow. The is_valid_filename function in wgtpkg-zip.c validates ZIP entry names but does not check for dot notation directory traversal sequences it only blocks absolute paths. The zread extraction function uses openat(workdirfd, filename, O_CREAT) which resolves dot notation values relative to the work directory, allowing files to be written anywhere on the filesystem. Critically, in function install_widget in file wgtpkg-install.c, extraction via zread occurs BEFORE signature verification via check_all_signatures. Even if signature verification fails, the error cleanup (remove_workdir) only deletes the temporary work directory files written outside via path traversal persist permanently.Show less

In the Linux kernel, the following vulnerability has been resolved: xfs: close crash window in attr dabtree inactivation When inactivating an inode with node-format extended attributes, xfs_attr3_node_inactive() invalidates all child leaf/node blocks via xfs_trans_binval(), but intentionally does not remove the corresponding entries from their parent node blocks. The implicit assumption is that xfs_attr_inactive() will truncate the entire attr fork to zero extents afterwards, so log recovery will never reach the root node and follow those stale pointers. However, if a log shutdown occurs after the leaf/node block cancellations commit but before the attr bmap truncation commits, this assumption breaks. Recovery replays the attr bmap intact (the inode still has attr fork extents), but suppresses replay of all cancelled leaf/node blocks, maybe leaving them as stale data on disk. On the next mount, xlog_recover_process_iunlinks() retries inactivation and attempts to read the root node via the attr bmap. If the root node was not replayed, reading the unreplayed root block triggers a metadata verification failure immediately; if it was replayed, following its child pointers to unreplayed child blocks triggers the same failure: XFS (pmem0): Metadata corruption detected at xfs_da3_node_read_verify+0x53/0x220, xfs_da3_node block 0x78 XFS (pmem0): Unmount and run xfs_repair XFS (pmem0): First 128 bytes of corrupted metadata buffer: 00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ XFS (pmem0): metadata I/O error in "xfs_da_read_buf+0x104/0x190" at daddr 0x78 len 8 error 117 Fix this in two places: In xfs_attr3_node_inactive(), after calling xfs_trans_binval() on a child block, immediately remove the entry that references it from the parent node in the same transaction. This eliminates the window where the parent holds a pointer to a cancelled block. Once all children are removed, the now-empty root node is converted to a leaf block within the same transaction. This node-to-leaf conversion is necessary for crash safety. If the system shutdown after the empty node is written to the log but before the second-phase bmap truncation commits, log recovery will attempt to verify the root block on disk. xfs_da3_node_verify() does not permit a node block with count == 0; such a block will fail verification and trigger a metadata corruption shutdown. on the other hand, leaf blocks are allowed to have this transient state. In xfs_attr_inactive(), split the attr fork truncation into two explicit phases. First, truncate all extents beyond the root block (the child extents whose parent references have already been removed above). Second, invalidate the root block and truncate the attr bmap to zero in a single transaction. The two operations in the second phase must be atomic: as long as the attr bmap has any non-zero length, recovery can follow it to the root block, so the root block invalidation must commit together with the bmap-to-zero truncation.Show less

In the Linux kernel, the following vulnerability has been resolved: net/packet: fix TOCTOU race on mmap'd vnet_hdr in tpacket_snd() In tpacket_snd(), when PACKET_VNET_HDR is enabled, vnet_hdr points directly into the mmap'd TX ring buffer shared with userspace. The kernel validates the header via __packet_snd_vnet_parse() but then re-reads all fields later in virtio_net_hdr_to_skb(). A concurrent userspace thread can modify the vnet_hdr fields between validation and use, bypassing all safety checks. The non-TPACKET path (packet_snd()) already correctly copies vnet_hdr to a stack-local variable. All other vnet_hdr consumers in the kernel (tun.c, tap.c, virtio_net.c) also use stack copies. The TPACKET TX path is the only caller of virtio_net_hdr_to_skb() that reads directly from user-controlled shared memory. Fix this by copying vnet_hdr from the mmap'd ring buffer to a stack-local variable before validation and use, consistent with the approach used in packet_snd() and all other callers.Show less

Wazuh is a free and open source platform used for threat prevention, detection, and response. From version 4.0.0 to before version 4.14.4, Wazuh's server API brute-force protection for POST /security/user/authenticate can be bypassed by sending concurrent authentication requests. Although the configured threshold (max_login_attempts, default 50) is enforced correctly for sequential requests, a parallel burst allows significantly more failed login attempts to be processed before the IP block is applied. This enables an attacker to perform more password guesses than the configured policy intends (e.g., 100 attempts processed where 50 should be allowed). This issue has been patched in version 4.14.4.Show less