CVE-2026-89602

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-89602", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.732Z", "datePublished": "2026-09-11T19:45:05.783Z", "dateUpdated": "2026-10-19T08:49:34.524Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:49:34.524Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nerofs: skip sufficiently large global buffers when resizing\n\nz_erofs_gbuf_nrpages is advanced only after every global buffer has been\ngrown. If a resize fails after some buffers were enlarged, a retry\nrevisits those enlarged buffers.\n\nRetrying the same size then returns -ENOMEM because alloc_pages_bulk()\nhas no pages to add and the unchanged return value is treated as a\nfailure. Retrying an intermediate size allocates a temporary pointer\narray smaller than gbuf->nrpages and copies more existing pointers than\nthe array can hold.\n\nSkip buffers that already satisfy the request. Once all remaining\nbuffers have caught up, advancing z_erofs_gbuf_nrpages again describes\nthe guaranteed minimum size across the pool."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - z_erofs_gbuf_growsize() runs only during a local EROFS mount (erofs_fc_get_tree \u2192 erofs_fc_fill_super \u2192 erofs_read_superblock \u2192 z_erofs_parse_cfgs \u2192 z_erofs_load_lz4_config) of a block, loop, or file-backed image. The LZ4 max_pclusterblks field is not parsed from a network protocol, so the vector is Local.\nAC:L - The attacker picks max_pclusterblks on two images (a large grow, then a strictly smaller size). After GFP_KERNEL alloc_pages_bulk()/vmap fails mid-loop, some per-CPU gbufs stay enlarged while z_erofs_gbuf_nrpages does not; the next intermediate mount then copies gbuf->nrpages pointers into a smaller tmp_pages array with no race. A max-size image plus memory pressure makes that partial failure attacker-inducible.\nPR:N - Crafting and supplying the malicious EROFS images needs no account or capability on the target. erofs_fs_type lacks FS_USERNS_MOUNT, so the CAP_SYS_ADMIN mount is done by a victim, automounter, or container runtime (OCI/Nydus/Android image handling), matching other crafted-image EROFS CVEs.\nUI:R - mount_capable() requires CAP_SYS_ADMIN in the initial user namespace because EROFS is not FS_USERNS_MOUNT. A separate user, automounter, or container runtime must mount the attacker-supplied images before z_erofs_gbuf_growsize() runs.\nS:U - The heap overflow corrupts kmalloc objects inside the host kernel. That is standard kernel memory corruption within one security authority, not a VM escape, IOMMU bypass, or other cross-boundary impact.\nC:H - The copy loop writes a nearly page-count-sized run of struct page * values past the kmalloc tmp_pages array (up to hundreds of pointers when max_pclusterblks is 256). That slab corruption can be turned into an arbitrary-read primitive against adjacent objects, so confidentiality impact is High.\nI:H - This is a kernel heap out-of-bounds write whose length is chosen by the two image sizes, smashing adjacent slab objects with kernel page pointers. Out-of-bounds writes are exploitable for arbitrary write and control-flow hijacking, so integrity impact is High.\nA:H - Overwriting adjacent kmalloc metadata and objects causes a kernel oops or panic. Independently, retrying the same size after a partial grow treats a full tmp_pages array as -ENOMEM and leaves the pool stuck, so later EROFS mounts fail until reboot."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/erofs/zutil.c"], "versions": [{"version": "d6db47e571dcaecaeaafa8840d00ae849ae3907b", "lessThan": "3fbdd15d5830f52661eb78be95058d101cb0c2cb", "status": "affected", "versionType": "git"}, {"version": "d6db47e571dcaecaeaafa8840d00ae849ae3907b", "lessThan": "7267557ce98ccd07faaf3bc86382448950cc4ff6", "status": "affected", "versionType": "git"}, {"version": "d6db47e571dcaecaeaafa8840d00ae849ae3907b", "lessThan": "7f4a89d4f0d6acaf4b756c31de48f2109a257b70", "status": "affected", "versionType": "git"}, {"version": "d6db47e571dcaecaeaafa8840d00ae849ae3907b", "lessThan": "a7d097cf01301c5da37927c8f26123d006f0fd8a", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/erofs/zutil.c"], "versions": [{"version": "6.10", "status": "affected"}, {"version": "0", "lessThan": "6.10", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.111", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.51", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.4", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3", "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:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "6.12.111"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "6.18.51"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "7.2.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/3fbdd15d5830f52661eb78be95058d101cb0c2cb"}, {"url": "https://git.kernel.org/stable/c/7267557ce98ccd07faaf3bc86382448950cc4ff6"}, {"url": "https://git.kernel.org/stable/c/7f4a89d4f0d6acaf4b756c31de48f2109a257b70"}, {"url": "https://git.kernel.org/stable/c/a7d097cf01301c5da37927c8f26123d006f0fd8a"}], "title": "erofs: skip sufficiently large global buffers when resizing", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/erofs/zutil.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "3fbdd15d5830f52661eb78be95058d101cb0c2cb", "status": "affected", "version": "d6db47e571dcaecaeaafa8840d00ae849ae3907b", "versionType": "git"}, {"lessThan": "7267557ce98ccd07faaf3bc86382448950cc4ff6", "status": "affected", "version": "d6db47e571dcaecaeaafa8840d00ae849ae3907b", "versionType": "git"}, {"lessThan": "7f4a89d4f0d6acaf4b756c31de48f2109a257b70", "status": "affected", "version": "d6db47e571dcaecaeaafa8840d00ae849ae3907b", "versionType": "git"}, {"lessThan": "a7d097cf01301c5da37927c8f26123d006f0fd8a", "status": "affected", "version": "d6db47e571dcaecaeaafa8840d00ae849ae3907b", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/erofs/zutil.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.10"}, {"lessThan": "6.10", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.111", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.51", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.4", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3", "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\nerofs: skip sufficiently large global buffers when resizing\n\nz_erofs_gbuf_nrpages is advanced only after every global buffer has been\ngrown. If a resize fails after some buffers were enlarged, a retry\nrevisits those enlarged buffers.\n\nRetrying the same size then returns -ENOMEM because alloc_pages_bulk()\nhas no pages to add and the unchanged return value is treated as a\nfailure. Retrying an intermediate size allocates a temporary pointer\narray smaller than gbuf->nrpages and copies more existing pointers than\nthe array can hold.\n\nSkip buffers that already satisfy the request. Once all remaining\nbuffers have caught up, advancing z_erofs_gbuf_nrpages again describes\nthe guaranteed minimum size across the pool."}], "id": "CVE-2026-89602", "lastModified": "2026-10-19T09:17:56.743", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2026-09-11T20:19:45.117", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/3fbdd15d5830f52661eb78be95058d101cb0c2cb"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/7267557ce98ccd07faaf3bc86382448950cc4ff6"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/7f4a89d4f0d6acaf4b756c31de48f2109a257b70"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a7d097cf01301c5da37927c8f26123d006f0fd8a"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: Linux kernel: erofs memory corruption during global buffer resizing", "id": "2532403", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2532403"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.0", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H", "status": "draft"}, "cwe": "CWE-787", "details": ["A flaw was found in the `erofs` (Enhanced Read-Only File System) component of the Linux kernel. This vulnerability occurs when resizing global buffers, specifically if a resize operation fails after some buffers have already been enlarged. A subsequent retry can lead to memory corruption by attempting to copy more data than an allocated buffer can hold. Additionally, retrying with the same size can result in an out-of-memory error, causing a denial of service."], "name": "CVE-2026-89602", "public_date": "2026-09-11T19:45:05Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-89602\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-89602\nhttps://git.kernel.org/stable/c/7267557ce98ccd07faaf3bc86382448950cc4ff6\nhttps://git.kernel.org/stable/c/7f4a89d4f0d6acaf4b756c31de48f2109a257b70\nhttps://git.kernel.org/stable/c/a7d097cf01301c5da37927c8f26123d006f0fd8a"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[d6db47e571dcaecaeaafa8840d00ae849ae3907b,7267557ce98ccd07faaf3bc86382448950cc4ff6)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[d6db47e571dcaecaeaafa8840d00ae849ae3907b,7f4a89d4f0d6acaf4b756c31de48f2109a257b70)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[d6db47e571dcaecaeaafa8840d00ae849ae3907b,a7d097cf01301c5da37927c8f26123d006f0fd8a)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "6.10"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,6.10)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.51,7.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.4,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3-rc1,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-09-12T09:30:13.016527+00:00", "updated": "2026-09-15T21:30:16.437121+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}