CVE-2026-80959

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-80959", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-26T14:34:25.809Z", "datePublished": "2026-09-11T19:42:26.514Z", "dateUpdated": "2026-10-19T08:45:43.213Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:45:43.213Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndm-pcache: bound the persisted tail-position offset\n\ncache_pos_decode() takes the persisted key_tail and dirty_tail seg_off from\nthe cache device and addresses within the segment with it. A seg_off at or\npast the segment data_size, controllable by whoever supplies the device\n(CAP_SYS_ADMIN), reads past the segment data.\n\nReject a decoded seg_off that is not below the segment data_size."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - The unbounded tail offset is consumed only when a local caller loads a dm-pcache table (ctl_ioctl \u2192 table_load \u2192 dm_pcache_ctr \u2192 pcache_cache_start \u2192 cache_tail_init \u2192 cache_pos_decode) from a supplied DAX cache device; no network, Bluetooth, or USB receive path parses this metadata.\nAC:L - The attacker fully controls the cache device and can forge key_tail/dirty_tail pos_onmedia with a valid CRC (public PCACHE_CRC_SEED), so cache_pos_decode() deterministically accepts an out-of-range seg_off; no race or uninfluenced victim state is required.\nPR:L - dm-ioctl.c gates table load with capable(CAP_SYS_ADMIN); kernel-CNA scoring treats that delegated capability (privileged containers, LVM/storage helpers) as Low rather than exclusive init-namespace root, and the attacker supplies the cache/backing devices on the pcache table.\nUI:N - The attacker performs every step itself: craft the persisted tail positions on a DAX cache device and issue DM_TABLE_LOAD for a pcache target; no other user must mount media, open files, or otherwise interact.\nS:U - The out-of-bounds pmem/kernel access and resulting oops stay inside the host kernel device-mapper/pcache mapping; this is not a VM escape, IOMMU bypass, or other cross-authority boundary.\nC:H - cache_replay(), writeback and GC copy ksets via copy_mc_to_kernel from cache_pos_addr() (segment.data plus the attacker-controlled u32 seg_off) for up to PCACHE_KSET_ONMEDIA_SIZE_MAX bytes, an unbounded over-read past segment data into later pmem or adjacent kernel VA, not a few-byte leak.\nI:H - A seg_off at data_size makes append_last_kset() memcpy_flushcache a kset into the next 16MiB segment's control metadata; a larger seg_off underflows u32 cache_seg_remain() so later key-head writes become arbitrary-offset stores through the DAX mapping, an out-of-bounds write primitive.\nA:H - cache_pos_advance() hits BUG_ON(cache_seg_remain(pos) < len) when a tail sits at data_size, and a huge seg_off makes copy_mc_to_kernel/memcpy_flushcache walk off the DAX mapping into unmapped kernel VA, oopsing or panicking the host."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/md/dm-pcache/cache.c"], "versions": [{"version": "1d57628ff95b32d5cfa8d8f50e07690c161e9cf0", "lessThan": "ffd9a214a94f9928e54856f42b1cc3e33fb10e36", "status": "affected", "versionType": "git"}, {"version": "1d57628ff95b32d5cfa8d8f50e07690c161e9cf0", "lessThan": "8bf7a06ca3c1611809725f58cfd573f2ffbda75f", "status": "affected", "versionType": "git"}, {"version": "1d57628ff95b32d5cfa8d8f50e07690c161e9cf0", "lessThan": "d1898576090a10d2ac2715218a652e78fb65a6b0", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/md/dm-pcache/cache.c"], "versions": [{"version": "6.18", "status": "affected"}, {"version": "0", "lessThan": "6.18", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.50", "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": "6.18", "versionEndExcluding": "6.18.50"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.18", "versionEndExcluding": "7.2.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.18", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/ffd9a214a94f9928e54856f42b1cc3e33fb10e36"}, {"url": "https://git.kernel.org/stable/c/8bf7a06ca3c1611809725f58cfd573f2ffbda75f"}, {"url": "https://git.kernel.org/stable/c/d1898576090a10d2ac2715218a652e78fb65a6b0"}], "title": "dm-pcache: bound the persisted tail-position offset", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["drivers/md/dm-pcache/cache.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "ffd9a214a94f9928e54856f42b1cc3e33fb10e36", "status": "affected", "version": "1d57628ff95b32d5cfa8d8f50e07690c161e9cf0", "versionType": "git"}, {"lessThan": "8bf7a06ca3c1611809725f58cfd573f2ffbda75f", "status": "affected", "version": "1d57628ff95b32d5cfa8d8f50e07690c161e9cf0", "versionType": "git"}, {"lessThan": "d1898576090a10d2ac2715218a652e78fb65a6b0", "status": "affected", "version": "1d57628ff95b32d5cfa8d8f50e07690c161e9cf0", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["drivers/md/dm-pcache/cache.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.18"}, {"lessThan": "6.18", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.50", "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\ndm-pcache: bound the persisted tail-position offset\n\ncache_pos_decode() takes the persisted key_tail and dirty_tail seg_off from\nthe cache device and addresses within the segment with it. A seg_off at or\npast the segment data_size, controllable by whoever supplies the device\n(CAP_SYS_ADMIN), reads past the segment data.\n\nReject a decoded seg_off that is not below the segment data_size."}], "id": "CVE-2026-80959", "lastModified": "2026-10-19T09:17:27.390", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/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": "2026-09-11T20:19:01.750", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/8bf7a06ca3c1611809725f58cfd573f2ffbda75f"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/d1898576090a10d2ac2715218a652e78fb65a6b0"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/ffd9a214a94f9928e54856f42b1cc3e33fb10e36"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: Linux kernel dm-pcache: Out-of-bounds read via malicious cache device input", "id": "2532361", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2532361"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.1", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:H", "status": "draft"}, "cwe": "CWE-125", "details": ["A flaw was found in the Linux kernel's device-mapper persistent cache (dm-pcache) component. A local attacker with administrative privileges (CAP_SYS_ADMIN) could provide a specially crafted cache device, leading to an out-of-bounds read. This vulnerability allows reading past the intended segment data, which may result in information disclosure or system instability."], "name": "CVE-2026-80959", "public_date": "2026-09-11T19:42:26Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-80959\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-80959\nhttps://git.kernel.org/stable/c/8bf7a06ca3c1611809725f58cfd573f2ffbda75f\nhttps://git.kernel.org/stable/c/d1898576090a10d2ac2715218a652e78fb65a6b0\nhttps://git.kernel.org/stable/c/ffd9a214a94f9928e54856f42b1cc3e33fb10e36"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1d57628ff95b32d5cfa8d8f50e07690c161e9cf0,ffd9a214a94f9928e54856f42b1cc3e33fb10e36)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1d57628ff95b32d5cfa8d8f50e07690c161e9cf0,8bf7a06ca3c1611809725f58cfd573f2ffbda75f)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1d57628ff95b32d5cfa8d8f50e07690c161e9cf0,d1898576090a10d2ac2715218a652e78fb65a6b0)"}}], "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": "semver", "value": "6.18"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,6.18)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[6.18.50,6.18.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2.4,7.2.*]"}}, {"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": "2026-09-12T02:45:06.471167+00:00", "updated": "2026-09-21T02:45:08.184832+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}