{"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":"2026-09-14T12:01:47.069Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-14T12:01:47.069Z"},"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-rc1","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-rc1"}]}]}],"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"}}}}