{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-89652", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.742Z", "datePublished": "2026-09-11T19:45:42.443Z", "dateUpdated": "2026-10-19T08:50:23.873Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:50:23.873Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nceph: bound copied dentry name length in NFS export get_name\n\nceph_get_name() copies the MDS-supplied name into the caller's\nNAME_MAX-sized buffer with memcpy(name, rinfo->dname, rinfo->dname_len)\nand then writes name[rinfo->dname_len] = 0, without checking dname_len\nagainst NAME_MAX. A malicious or buggy MDS that returns a LOOKUPNAME reply\nwith dname_len > NAME_MAX overflows the buffer. __get_snap_name() copies\nrde->name / rde->name_len the same unchecked way.\n\nImpact: a malicious or compromised Ceph MDS overflows the NAME_MAX name\nbuffer in a client's NFS-export get_name path, a slab out-of-bounds write\nreported by KASAN. Reachable when a CephFS mount is re-exported over NFS.\n\nAdd ceph_export_copy_name(), which rejects lengths above NAME_MAX with\n-ENAMETOOLONG before the copy, and use it in both ceph_get_name() and\n__get_snap_name()." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL" }, "scenarios": [ { "lang": "en", "value": "AV:N - ceph_get_name() copies LOOKUPNAME/LSSNAP dentry names from a Ceph MDS reply over TCP, and nfsd reaches that callback via exportfs_decode_fh_raw() when CephFS is re-exported, so a remote MDS (or NFS client against such a gateway) hits the overflow on the network path.\nAC:L - A malicious MDS fully controls dname_len and the name bytes. nfsd lookup of a Ceph directory uses d_obtain_alias() then reconnect_path(), which deterministically calls get_name; no race, rare config, or uncontrollable layout is required.\nPR:N - No local account or capability on the victim is needed. A compromised or malicious MDS supplies the overflowing name, and on NFS-reexported CephFS any remote NFS client can force LOOKUPNAME by presenting a directory filehandle.\nUI:N - Once CephFS is mounted and re-exported over NFS, nfsd directory filehandle resolution automatically issues LOOKUPNAME and copies the MDS reply; no extra victim mount, click, or interactive step is required at exploit time.\nS:U - The overflow corrupts kernel stack/memory on the NFS/Ceph client host and does not cross a VM, IOMMU, or other security-authority boundary.\nC:H - Unbounded memcpy of MDS-controlled name bytes past the NAME_MAX+1 exportfs buffer is memory corruption that can overwrite adjacent kernel objects and be leveraged for arbitrary disclosure.\nI:H - Attacker-controlled length and contents overflow the NAME_MAX+1 stack buffer in exportfs_decode_fh_raw(), enabling an arbitrary write and control-flow hijacking.\nA:H - The same out-of-bounds write of a 256-byte name buffer by an MDS-chosen length, reported as a KASAN OOB write, reliably oopses or panics the kernel." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/ceph/export.c" ], "versions": [ { "version": "19913b4eac4a230dccb548931358398f45dabe4c", "lessThan": "a294064e0e0f81ea607b2f019e16888aa1b0a011", "status": "affected", "versionType": "git" }, { "version": "19913b4eac4a230dccb548931358398f45dabe4c", "lessThan": "61d9f27b191b838b96b697ce0bfaee39a138243a", "status": "affected", "versionType": "git" }, { "version": "19913b4eac4a230dccb548931358398f45dabe4c", "lessThan": "06fb5e623cdc2402d6bb29be94d9beb9a826ffec", "status": "affected", "versionType": "git" }, { "version": "19913b4eac4a230dccb548931358398f45dabe4c", "lessThan": "e7c2fd3893a7f7fcd7e8cf0b2c6348bb1e893df6", "status": "affected", "versionType": "git" }, { "version": "19913b4eac4a230dccb548931358398f45dabe4c", "lessThan": "eff8013c5a8916613c742ae5a2cc341cb605c0ae", "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/ceph/export.c" ], "versions": [ { "version": "3.15", "status": "affected" }, { "version": "0", "lessThan": "3.15", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.157", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.109", "lessThanOrEqual": "6.12.*", "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": "3.15", "versionEndExcluding": "6.6.157" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.15", "versionEndExcluding": "6.12.109" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.15", "versionEndExcluding": "6.18.50" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.15", "versionEndExcluding": "7.2.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.15", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/a294064e0e0f81ea607b2f019e16888aa1b0a011" }, { "url": "https://git.kernel.org/stable/c/61d9f27b191b838b96b697ce0bfaee39a138243a" }, { "url": "https://git.kernel.org/stable/c/06fb5e623cdc2402d6bb29be94d9beb9a826ffec" }, { "url": "https://git.kernel.org/stable/c/e7c2fd3893a7f7fcd7e8cf0b2c6348bb1e893df6" }, { "url": "https://git.kernel.org/stable/c/eff8013c5a8916613c742ae5a2cc341cb605c0ae" } ], "title": "ceph: bound copied dentry name length in NFS export get_name", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2026-89652", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "yes" }, { "Technical Impact": "total" } ], "version": "2.0.3", "timestamp": "2026-10-16T19:25:18.510719Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T19:26:46.828Z" } } ] } }