{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-89654", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.743Z", "datePublished": "2026-09-11T19:45:44.086Z", "dateUpdated": "2026-09-11T19:45:44.086Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-09-11T19:45:44.086Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nceph: fix UAF in check_new_map() on session freed during unlock\n\ncheck_new_map() iterates mdsc->sessions[] and for each active session\ndrops mdsc->mutex to perform per-session operations. The forced-close\npath (rank removed from map) correctly takes a reference on s via\nceph_get_mds_session() before releasing mdsc->mutex, but three other\npaths do not:\n\n Path A (address changed): mutex_unlock \u2192 mutex_lock(&s->s_mutex)\n Path B (reconnect): mutex_unlock \u2192 send_mds_reconnect(mdsc, s)\n Path C (active transition): mutex_unlock \u2192 mutex_lock(&s->s_mutex)\n\nWithout the extra reference, another thread can acquire mdsc->mutex\nduring the unlock window, call __unregister_session() which drops the\nlast reference on s, and free it. The original thread then accesses\nfreed memory via s->s_mutex.\n\nFix by adding ceph_get_mds_session(s) before each mutex_unlock and\nceph_put_mds_session(s) after the corresponding mutex_lock, matching\nthe pattern already used in the forced-close path.\n\nRace timeline (Path A):\n\n Thread A (check_new_map) Thread B (another map update\n holds mdsc->mutex or session teardown)\n -------------------------- --------------------------\n s = mdsc->sessions[i]\n (refcount == 1, held only by\n sessions[] array)\n\n mutex_unlock(&mdsc->mutex)\n ---> acquires mdsc->mutex\n __unregister_session(mdsc, s)\n sessions[i] = NULL\n ceph_put_mds_session(s)\n refcount: 1 -> 0\n kfree(s) <--- freed!\n\n mutex_lock(&s->s_mutex)\n UAF on freed s->s_mutex"}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/ceph/mds_client.c"], "versions": [{"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "21d5be092d947f8d83f76f7ebf3989e7e9230a98", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "ee611a7509554c4ca1f54f6aefe592fb1df7ea70", "status": "affected", "versionType": "git"}, {"version": "0", "lessThan": "7.2.4", "status": "affected", "versionType": "semver"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/ceph/mds_client.c"], "versions": [{"version": "7.2.4", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3-rc1", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "7.2.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "7.3-rc1"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/21d5be092d947f8d83f76f7ebf3989e7e9230a98"}, {"url": "https://git.kernel.org/stable/c/ee611a7509554c4ca1f54f6aefe592fb1df7ea70"}], "title": "ceph: fix UAF in check_new_map() on session freed during unlock", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/ceph/mds_client.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "21d5be092d947f8d83f76f7ebf3989e7e9230a98", "status": "affected", "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "versionType": "git"}, {"lessThan": "ee611a7509554c4ca1f54f6aefe592fb1df7ea70", "status": "affected", "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "versionType": "git"}, {"lessThan": "7.2.4", "status": "affected", "version": "0", "versionType": "semver"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/ceph/mds_client.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.4", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3-rc1", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nceph: fix UAF in check_new_map() on session freed during unlock\n\ncheck_new_map() iterates mdsc->sessions[] and for each active session\ndrops mdsc->mutex to perform per-session operations. The forced-close\npath (rank removed from map) correctly takes a reference on s via\nceph_get_mds_session() before releasing mdsc->mutex, but three other\npaths do not:\n\n Path A (address changed): mutex_unlock \u2192 mutex_lock(&s->s_mutex)\n Path B (reconnect): mutex_unlock \u2192 send_mds_reconnect(mdsc, s)\n Path C (active transition): mutex_unlock \u2192 mutex_lock(&s->s_mutex)\n\nWithout the extra reference, another thread can acquire mdsc->mutex\nduring the unlock window, call __unregister_session() which drops the\nlast reference on s, and free it. The original thread then accesses\nfreed memory via s->s_mutex.\n\nFix by adding ceph_get_mds_session(s) before each mutex_unlock and\nceph_put_mds_session(s) after the corresponding mutex_lock, matching\nthe pattern already used in the forced-close path.\n\nRace timeline (Path A):\n\n Thread A (check_new_map) Thread B (another map update\n holds mdsc->mutex or session teardown)\n -------------------------- --------------------------\n s = mdsc->sessions[i]\n (refcount == 1, held only by\n sessions[] array)\n\n mutex_unlock(&mdsc->mutex)\n ---> acquires mdsc->mutex\n __unregister_session(mdsc, s)\n sessions[i] = NULL\n ceph_put_mds_session(s)\n refcount: 1 -> 0\n kfree(s) <--- freed!\n\n mutex_lock(&s->s_mutex)\n UAF on freed s->s_mutex"}], "id": "CVE-2026-89654", "lastModified": "2026-09-11T20:19:51.540", "metrics": {}, "published": "2026-09-11T20:19:51.540", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/21d5be092d947f8d83f76f7ebf3989e7e9230a98"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/ee611a7509554c4ca1f54f6aefe592fb1df7ea70"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: ceph: Linux kernel Ceph: Use-after-free vulnerability in session management", "id": "2532045", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2532045"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.7", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-364", "details": ["A flaw was found in the Ceph file system component of the Linux kernel. A race condition exists in the `check_new_map()` function during session handling. This allows a local attacker to exploit a use-after-free vulnerability by freeing a session while another thread attempts to access it. This could lead to a denial of service or potentially arbitrary code execution."], "name": "CVE-2026-89654", "package_state": [{"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "openshift/ose-rhel-coreos-8", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "openshift/ose-rhel-coreos-9", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-09-11T19:45:44Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-89654\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-89654\nhttps://git.kernel.org/stable/c/21d5be092d947f8d83f76f7ebf3989e7e9230a98\nhttps://git.kernel.org/stable/c/ee611a7509554c4ca1f54f6aefe592fb1df7ea70"], "threat_severity": "Moderate"}

{}