Openbsd

An issue was discovered in the kernel in OpenBSD 6.6. The WEP, WPA, WPA2, and WPA3 implementations treat fragmented frames as full frames. An adversary can abuse this to inject arbitrary network packets, independent of the network configuration.Show less

ssh-agent in OpenSSH before 8.5 has a double free that may be relevant in a few less-common scenarios, such as unconstrained agent-socket access on a legacy operating system, or the forwarding of an agent to an attacker-controlled host.Show less

scp in OpenSSH through 8.3p1 allows command injection in the scp.c toremote function, as demonstrated by backtick characters in the destination argument. NOTE: the vendor reportedly has stated that they intentionally omit validation of "anomalous argument transfers" because that could "stand a great chance of breaking existing workflows."Show less

The client side in OpenSSH 5.7 through 8.4 has an Observable Discrepancy leading to an information leak in the algorithm negotiation. This allows man-in-the-middle attackers to target initial connection attempts (where no host key for the server has been cached by the client). NOTE: some reports state that 8.5 and 8.6 are also affected.Show less

The scp client in OpenSSH 8.2 incorrectly sends duplicate responses to the server upon a utimes system call failure, which allows a malicious unprivileged user on the remote server to overwrite arbitrary files in the client's download directory by creating a crafted subdirectory anywhere on the remote server. The victim must use the command scp -rp to download a file hierarchy containing, anywhere inside, this crafted subdirectory. NOTE: the vendor points out that "this attack can achieve no more than a hostile peer is already able to achieve within the scp protocol" and "utimes does not fail under normal circumstances.Show less

smtp_mailaddr in smtp_session.c in OpenSMTPD 6.6, as used in OpenBSD 6.6 and other products, allows remote attackers to execute arbitrary commands as root via a crafted SMTP session, as demonstrated by shell metacharacters in a MAIL FROM field. This affects the "uncommented" default configuration. The issue exists because of an incorrect return value upon failure of input validation.Show less

Off-by-one error in the OBJ_obj2txt function in LibreSSL before 2.3.1 allows remote attackers to cause a denial of service (program crash) or possible execute arbitrary code via a crafted X.509 certificate, which triggers a stack-based buffer overflow. Note: this vulnerability exists because of an incorrect fix for CVE-2014-3508.Show less

OpenBSD through 6.6 allows local users to escalate to root because a check for LD_LIBRARY_PATH in setuid programs can be defeated by setting a very small RLIMIT_DATA resource limit. When executing chpass or passwd (which are setuid root), _dl_setup_env in ld.so tries to strip LD_LIBRARY_PATH from the environment, but fails when it cannot allocate memory. Thus, the attacker is able to execute their own library code as root.Show less

A vulnerability was discovered in Linux, FreeBSD, OpenBSD, MacOS, iOS, and Android that allows a malicious access point, or an adjacent user, to determine if a connected user is using a VPN, make positive inferences about the websites they are visiting, and determine the correct sequence and acknowledgement numbers in use, allowing the bad actor to inject data into the TCP stream. This provides everything that is needed for an attacker to hijack active connections inside the VPN tunnel.Show less

OpenBSD 6.6, in a non-default configuration where S/Key or YubiKey authentication is enabled, allows local users to become root by leveraging membership in the auth group. This occurs because root's file can be written to /etc/skey or /var/db/yubikey, and need not be owned by root.Show less

libc in OpenBSD 6.6 allows authentication bypass via the -schallenge username, as demonstrated by smtpd, ldapd, or radiusd. This is related to gen/auth_subr.c and gen/authenticate.c in libc (and login/login.c and xenocara/app/xenodm/greeter/verify.c).Show less

OpenSSH 7.7 through 7.9 and 8.x before 8.1, when compiled with an experimental key type, has a pre-authentication integer overflow if a client or server is configured to use a crafted XMSS key. This leads to memory corruption and local code execution because of an error in the XMSS key parsing algorithm. NOTE: the XMSS implementation is considered experimental in all released OpenSSH versions, and there is no supported way to enable it when building portable OpenSSH.Show less