{"id":"CVE-2026-93191","revision":"eceb98a21815453e9b3c227f906ff470","records":[{"revision":"eceb98a21815453e9b3c227f906ff470","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-93191","aliases":[],"title":"smack: fix incorrect task context in smack_msg_queue_msgrcv","description":"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 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)","state":0,"publishedAt":"2026-09-17T16:12:15.765+00:00","modifiedAt":"2026-10-19T09:07:03.807+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"security/smack/smack_lsm.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"e114e473771c848c3cfec05f0123e70f1cdbdc99\",\n                            \"lessThan\": \"4e49f997ef0c569e09b42aab6bd38c7c54ea095d\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"e114e473771c848c3cfec05f0123e70f1cdbdc99\",\n                            \"lessThan\": \"dbece6c2f80b0470d8d99d7a016827dce99ed6e3\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"e114e473771c848c3cfec05f0123e70f1cdbdc99\",\n                            \"lessThan\": \"7be4bd21c50afa83c93799b0f16cf5bfa493194e\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"e114e473771c848c3cfec05f0123e70f1cdbdc99\",\n                            \"lessThan\": \"ec47f4177046dfaaf1cebb15f4d2e7b543475daf\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"e114e473771c848c3cfec05f0123e70f1cdbdc99\",\n                            \"lessThan\": \"e35dc5a4ed6d1e536382d80c685187511ff248a1\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"e114e473771c848c3cfec05f0123e70f1cdbdc99\",\n                            \"lessThan\": \"c2ab27c2e11591524b1378c24ad18882a425d1fa\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"e114e473771c848c3cfec05f0123e70f1cdbdc99\",\n                            \"lessThan\": \"d02c55e3ea82e41ea2c2026e08201e5daa4d0cfe\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"e114e473771c848c3cfec05f0123e70f1cdbdc99\",\n                            \"lessThan\": \"fba3d32825f4bbc8e20f0cdc3b14df57965b8fe5\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"security/smack/smack_lsm.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"2.6.25\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"2.6.25\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.270\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.221\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.188\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.157\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.110\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.52\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.6\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/4e49f997ef0c569e09b42aab6bd38c7c54ea095d","https://git.kernel.org/stable/c/dbece6c2f80b0470d8d99d7a016827dce99ed6e3","https://git.kernel.org/stable/c/7be4bd21c50afa83c93799b0f16cf5bfa493194e","https://git.kernel.org/stable/c/ec47f4177046dfaaf1cebb15f4d2e7b543475daf","https://git.kernel.org/stable/c/e35dc5a4ed6d1e536382d80c685187511ff248a1","https://git.kernel.org/stable/c/c2ab27c2e11591524b1378c24ad18882a425d1fa","https://git.kernel.org/stable/c/d02c55e3ea82e41ea2c2026e08201e5daa4d0cfe","https://git.kernel.org/stable/c/fba3d32825f4bbc8e20f0cdc3b14df57965b8fe5"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-93191","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-93191","identifiers":["CVE-2026-93191"]},"retained":false,"historicalAffected":[]}],"coverage":[]}