{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2026-89650", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-89650", "idYear": 2026, "status": "PUBLISHED", "publishedAt": "2026-09-11T19:45:40.867Z", "updatedAt": "2026-10-19T08:50:21.912Z", "importedAt": "2026-10-24T01:58:35.090Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "ceph: bound num_export_targets array for mds info v2/v3", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nceph: bound num_export_targets array for mds info v2/v3\n\nceph_mdsmap_decode() in fs/ceph/mdsmap.c reads num_export_targets from\neach per-mds info record and advances the decode cursor by\nnum_export_targets * sizeof(u32) without first checking that many bytes\nremain. The only upper-bound check that catches a runaway cursor\n(*p > info_end) is gated on info_v >= 4, because info_end is left NULL\nfor info_v 2 and 3. When the monitor sends an MDS map whose per-mds\ninfo version is 2 or 3 with an oversized num_export_targets, the cursor\nmoves past the message front buffer and the later export-targets loop\ncalls the unchecked ceph_decode_32() on out-of-bounds memory.\n\nA kernel client processes CEPH_MSG_MDS_MAP from its monitor session\n(net/ceph/mon_client.c dispatches it; fs/ceph/super.c routes it to\nceph_mdsc_handle_mdsmap(), which sets end to the front buffer bound and\ncalls ceph_mdsmap_decode()). A malicious or compromised monitor, or an\non-path attacker on an unsigned/unencrypted messenger session, can\ntherefore drive an out-of-bounds read in the client kernel; on x86_64\nwith KASAN it is reported as a slab-out-of-bounds read in\nceph_mdsmap_decode(). The decoded values land in the internal\ninfo->export_targets[] array, so the consequence is a kernel\nout-of-bounds read, not an information leak to the attacker.\n\nImpact: a malicious or compromised Ceph monitor sending an MDS map with\na per-mds info version of 2 or 3 and an oversized num_export_targets\nfield triggers an out-of-bounds read in the CephFS client kernel.\n\nAdd a ceph_decode_need() for the export-targets array before advancing\nthe cursor, so the bound is enforced for every info_v >= 2, not only\ninfo_v >= 4. This mirrors the count-then-need idiom already used for\nm_data_pg_pools later in the same function.\n\nCompute the export-targets byte count with size_mul() and reuse that\nchecked length when advancing the cursor, so the attacker-controlled\nnum_export_targets multiplication fails closed on overflow rather than\nrelying on the later kcalloc() guard.", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "d463a43d69f4af85887671d76182437775fd1631", "status": "affected", "versionType": "git", "lessThan": "0c4bcc3ba7291d383b82ce1c2fe324f69a42da2d" }, { "version": "d463a43d69f4af85887671d76182437775fd1631", "status": "affected", "versionType": "git", "lessThan": "55a06b32438c222765138727d0a8164b103e8f0d" }, { "version": "d463a43d69f4af85887671d76182437775fd1631", "status": "affected", "versionType": "git", "lessThan": "eb3e1a1cb1634c76d59c5a9cb1a026fc69d40911" }, { "version": "d463a43d69f4af85887671d76182437775fd1631", "status": "affected", "versionType": "git", "lessThan": "3bf7dba8dba9a05774b846affec61a3624ddba38" }, { "version": "d463a43d69f4af85887671d76182437775fd1631", "status": "affected", "versionType": "git", "lessThan": "58c2d3e954c13694ef6e820a5e9456461bb9e7df" }, { "version": "d463a43d69f4af85887671d76182437775fd1631", "status": "affected", "versionType": "git", "lessThan": "332c444f4dc6fa1e8b8637c9e82d29e97f768656" }, { "version": "d463a43d69f4af85887671d76182437775fd1631", "status": "affected", "versionType": "git", "lessThan": "a3eb169ee297aa99670ba927c659990bd1e453f3" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "4.7", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "4.7" }, { "version": "5.15.221", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.188", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.157", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.109", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.18.50", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.18.*" }, { "version": "7.2.4", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "7.2.*" }, { "version": "7.3", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }