{"id":"CVE-2026-93191","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmack: fix incorrect task context in smack_msg_queue_msgrcv\n\nThe smack_msg_queue_msgrcv() function incorrectly checks\nthe permissions of the 'current' task instead of t…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmack: fix incorrect task context in smack_msg_queue_msgrcv\n\nThe smack_msg_queue_msgrcv() function incorrectly checks\nthe permissions of the 'current' task instead of t…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= e114e473771c848c3cfec05f0123e70f1cdbdc99 < 4e49f997ef0c569e09b42aab6bd38c7c54ea095d","Linux >= e114e473771c848c3cfec05f0123e70f1cdbdc99 < dbece6c2f80b0470d8d99d7a016827dce99ed6e3","Linux >= e114e473771c848c3cfec05f0123e70f1cdbdc99 < 7be4bd21c50afa83c93799b0f16cf5bfa493194e","Linux >= e114e473771c848c3cfec05f0123e70f1cdbdc99 < ec47f4177046dfaaf1cebb15f4d2e7b543475daf","Linux >= e114e473771c848c3cfec05f0123e70f1cdbdc99 < e35dc5a4ed6d1e536382d80c685187511ff248a1","Linux >= e114e473771c848c3cfec05f0123e70f1cdbdc99 < c2ab27c2e11591524b1378c24ad18882a425d1fa","Linux >= e114e473771c848c3cfec05f0123e70f1cdbdc99 < d02c55e3ea82e41ea2c2026e08201e5daa4d0cfe","Linux >= e114e473771c848c3cfec05f0123e70f1cdbdc99 < fba3d32825f4bbc8e20f0cdc3b14df57965b8fe5","Linux 2.6.25"],"published":"2026-09-17","updated":"2026-09-17","sourceUpdated":"2026-09-17T17:18:15.307","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-93191","references":[{"url":"https://git.kernel.org/stable/c/4e49f997ef0c569e09b42aab6bd38c7c54ea095d","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7be4bd21c50afa83c93799b0f16cf5bfa493194e","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/c2ab27c2e11591524b1378c24ad18882a425d1fa","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d02c55e3ea82e41ea2c2026e08201e5daa4d0cfe","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/dbece6c2f80b0470d8d99d7a016827dce99ed6e3","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e35dc5a4ed6d1e536382d80c685187511ff248a1","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ec47f4177046dfaaf1cebb15f4d2e7b543475daf","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/fba3d32825f4bbc8e20f0cdc3b14df57965b8fe5","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-09-17T16:21:47.725Z","epss":0.00196,"epssPercentile":0.09625,"slug":"CVE-2026-93191","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nsmack: fix incorrect task context in smack_msg_queue_msgrcv\n\nThe smack_msg_queue_msgrcv() function incorrectly checks\nthe permissions of the 'current' task instead of the\n'target' task.\n\nIn the msgsnd() syscall path, if a receiver is already waiting,\nthe pipelined_send() optimization is used to push the message\ndirectly to the receiver task:\n\n    ipc/msg.c`pipelined_send():\n    ` smp_store_release(&msr->r_msg, msg)\n\nIn this case, the 'sender' (current) task performs the check\non behalf of the 'receiver' task (msr->r_tsk, passed as the\n'target' parameter):\n\n  ipc/msg.c`pipelined_send():\n  ` security_msg_queue_msgrcv(,, target := msr->r_tsk,,)\n\nHowever, smack_msg_queue_msgrcv() ignores the 'target' and\nchecks 'current':\n\n  smack_msg_queue_msgrcv(…)\n  ` smk_curacc_msq(isp, MAY_READWRITE); // current task\n\n'current' MAY satisfy smack_msg_queue_msgrcv r/w requirement,\nbut 'target' (the receiver task) might NOT;\nas a result, an unauthorized receiver gets the message,\nviolating MAC policy.\n\nTest:\n1) create a sysv message queue with label “foo”\n2) echo \"bar foo r\" >/smack/load2\n3) msgrcv(,,,0,MSG_NOERROR) in \"bar\"-labeled task.\n    The task is waiting for the messages ...\n4) msgsnd() from a \"foo\"-labeled task:\n\"bar\"-labeled task gets the message.\n\nThis patch fixes the issue by checking permission on the\n'target' task instead of 'current'.\n\n(2008-02-04, Casey Schaufler)\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}