{ "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-2026-80808", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-80808", "idYear": 2026, "status": "PUBLISHED", "publishedAt": "2026-09-04T15:13:28.562Z", "updatedAt": "2026-10-19T08:44:01.677Z", "importedAt": "2026-10-24T01:58:30.346Z", "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": "ext4: stop retrying saturated xattr cache entries", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: stop retrying saturated xattr cache entries\n\next4_xattr_block_set() retries when a cache entry selected for reuse\nhas a saturated reference count after taking the buffer lock. The retry\nreturns to the mbcache lookup without making that entry ineligible, so\nit can select the same unusable entry indefinitely. A task spinning\nthere can hold the parent directory's i_rwsem and leave concurrent\nrmdir callers blocked.\n\nNormally a reusable entry has a reference count below\nEXT4_XATTR_REFCOUNT_MAX because the count and MBE_REUSABLE_B are\nupdated under the same buffer lock. A corrupted filesystem can violate\nthat invariant. The syzbot reproducer reports allocator and xattr\ncorruption before triggering this retry loop.\n\nCheck the untrusted on-disk count before incrementing it, avoiding\noverflow, and clear MBE_REUSABLE_B when it is already saturated. The\nnext lookup then skips the entry that was just proven unusable. This\nmirrors the normal transition at EXT4_XATTR_REFCOUNT_MAX; the release\npath marks the entry reusable again on the exact 1024-to-1023\ntransition.\n\nUsing the same QEMU harness and guest parameters, current unpatched\nLinux hung in 6 of 8 420-second trials with the do_rmdir signature;\nrepresentative NMI backtraces caught the owner spinning in\next4_xattr_block_set(). The patched kernel completed 28 of 28 trials\nwithout a hung-task report; the final twelve trials exercised the\nreviewed overflow-safe form of the change. syzbot's patch testing also\ncompleted without reproducing the hang.", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "1a56cd972ce121b6cf2517a47a578782bbd2ec95", "status": "affected", "versionType": "git", "lessThan": "119a2f053242ed75bdd2ebc95baf3ae7db6ccacf" }, { "version": "1be97463696c7291a3e1547614e96432b0bd3add", "status": "affected", "versionType": "git", "lessThan": "61631352a5b405c89be579de00903b72e6888aa4" }, { "version": "65f8b80053a1b2fd602daa6814e62d6fa90e5e9b", "status": "affected", "versionType": "git", "lessThan": "8865cd664484517703df5c18a965dc3227572b87" }, { "version": "65f8b80053a1b2fd602daa6814e62d6fa90e5e9b", "status": "affected", "versionType": "git", "lessThan": "a40c45268f4358207aa9c53764fed2e05f62986a" }, { "version": "65f8b80053a1b2fd602daa6814e62d6fa90e5e9b", "status": "affected", "versionType": "git", "lessThan": "889ec86464d261f026f6c334040cfc6c58c99d58" }, { "version": "65f8b80053a1b2fd602daa6814e62d6fa90e5e9b", "status": "affected", "versionType": "git", "lessThan": "4902a5cba21aeaf91e6b29e20e0967a5f6abdcd9" }, { "version": "65f8b80053a1b2fd602daa6814e62d6fa90e5e9b", "status": "affected", "versionType": "git", "lessThan": "55ee6533c1db7f7656fa8dd19637f3f8b8c08dc5" }, { "version": "65f8b80053a1b2fd602daa6814e62d6fa90e5e9b", "status": "affected", "versionType": "git", "lessThan": "dbd4aea175ad3c46436acb251e817b4374628072" }, { "version": "65f8b80053a1b2fd602daa6814e62d6fa90e5e9b", "status": "affected", "versionType": "git", "lessThan": "54b6bd40898de7906acb2bccc9a96d1b8e6b4323" }, { "version": "98953044b3cdb2cb7d82e7365b659e2ed4f4ca4d", "status": "affected", "versionType": "git" }, { "version": "af8ecc8d20e72130771cc076bce7fcf17ccda6c4", "status": "affected", "versionType": "git" }, { "version": "c6fac5cf5a5098732623bcd00a8a3eb9f5465144", "status": "affected", "versionType": "git" }, { "version": "96fa141fa295ae9428da73c56c9852053b575c04", "status": "affected", "versionType": "git" }, { "version": "5.10.163", "status": "affected", "versionType": "semver", "lessThan": "5.10.267" }, { "version": "5.15.61", "status": "affected", "versionType": "semver", "lessThan": "5.15.218" }, { "version": "4.19.270", "status": "affected", "versionType": "semver", "lessThan": "4.20" }, { "version": "5.4.229", "status": "affected", "versionType": "semver", "lessThan": "5.5" }, { "version": "5.18.18", "status": "affected", "versionType": "semver", "lessThan": "5.19" }, { "version": "5.19.2", "status": "affected", "versionType": "semver", "lessThan": "5.20" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "6.0", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "6.0" }, { "version": "5.10.267", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.218", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.185", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.154", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.106", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.18.47", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.18.*" }, { "version": "7.1.11", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "7.1.*" }, { "version": "7.2.1", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "7.2.*" }, { "version": "7.3", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }