systemd-tmpfiles in systemd through 237 mishandles symlinks present in non-terminal path components, which allows local users to obtain ownership of arbitrary files via vectors involving creation of a directory and a file under that directory, and later replacing that directory with a symlink. This occurs even if the fs.protected_symlinks sysctl is turned on.

systemd-tmpfiles in systemd before 237 attempts to support ownership/permission changes on hardlinked files even if the fs.protected_hardlinks sysctl is turned off, which allows local users to bypass intended access restrictions via vectors involving a hard link to a file for which the user lacks write access, as demonstrated by changing the ownership of the /etc/passwd file.

The tcpmss_mangle_packet function in net/netfilter/xt_TCPMSS.c in the Linux kernel before 4.11, and 4.9.x before 4.9.36, allows remote attackers to cause a denial of service (use-after-free and memory corruption) or possibly have unspecified other impact by leveraging the presence of xt_TCPMSS in an iptables action.

The Salsa20 encryption algorithm in the Linux kernel before 4.14.8 does not correctly handle zero-length inputs, allowing a local attacker able to use the AF_ALG-based skcipher interface (CONFIG_CRYPTO_USER_API_SKCIPHER) to cause a denial of service (uninitialized-memory free and kernel crash) or have unspecified other impact by executing a crafted sequence of system calls that use the blkcipher_walk API. Both the generic implementation (crypto/salsa20_generic.c) and x86 implementation (arch/x86/crypto/salsa20_glue.c) of Salsa20 were vulnerable.

The HMAC implementation (crypto/hmac.c) in the Linux kernel before 4.14.8 does not validate that the underlying cryptographic hash algorithm is unkeyed, allowing a local attacker able to use the AF_ALG-based hash interface (CONFIG_CRYPTO_USER_API_HASH) and the SHA-3 hash algorithm (CONFIG_CRYPTO_SHA3) to cause a kernel stack buffer overflow by executing a crafted sequence of system calls that encounter a missing SHA-3 initialization.

Wi-Fi Protected Access (WPA and WPA2) that support 802.11v allows reinstallation of the Integrity Group Temporal Key (IGTK) when processing a Wireless Network Management (WNM) Sleep Mode Response frame, allowing an attacker within radio range to replay frames from access points to clients.

Wi-Fi Protected Access (WPA and WPA2) allows reinstallation of the Station-To-Station-Link (STSL) Transient Key (STK) during the PeerKey handshake, allowing an attacker within radio range to replay, decrypt, or spoof frames.

Wi-Fi Protected Access (WPA and WPA2) allows reinstallation of the Tunneled Direct-Link Setup (TDLS) Peer Key (TPK) during the TDLS handshake, allowing an attacker within radio range to replay, decrypt, or spoof frames.

Wi-Fi Protected Access (WPA and WPA2) that supports IEEE 802.11w allows reinstallation of the Integrity Group Temporal Key (IGTK) during the group key handshake, allowing an attacker within radio range to spoof frames from access points to clients.

Wi-Fi Protected Access (WPA and WPA2) that supports IEEE 802.11r allows reinstallation of the Pairwise Transient Key (PTK) Temporal Key (TK) during the fast BSS transmission (FT) handshake, allowing an attacker within radio range to replay, decrypt, or spoof frames.