Critical severity · published Sep 11, 2026
CVE-2026-89652
ceph: bound copied dentry name length in NFS export get_name
9.8
CVSS
0.5%
EPSS
No
On KEV
Description
In the Linux kernel, the following vulnerability has been resolved:
ceph: bound copied dentry name length in NFS export get_name
ceph_get_name() copies the MDS-supplied name into the caller's
NAME_MAX-sized buffer with memcpy(name, rinfo->dname, rinfo->dname_len)
and then writes name[rinfo->dname_len] = 0, without checking dname_len
against NAME_MAX. A malicious or buggy MDS that returns a LOOKUPNAME reply
with dname_len > NAME_MAX overflows the buffer. __get_snap_name() copies
rde->name / rde->name_len the same unchecked way.
Impact: a malicious or compromised Ceph MDS overflows the NAME_MAX name
buffer in a client's NFS-export get_name path, a slab out-of-bounds write
reported by KASAN. Reachable when a CephFS mount is re-exported over NFS.
Add ceph_export_copy_name(), which rejects lengths above NAME_MAX with
-ENAMETOOLONG before the copy, and use it in both ceph_get_name() and
__get_snap_name().
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 39% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Linux · Linux
19913b4eac4a230dccb548931358398f45dabe4c before a294064e0e0f81ea607b2f019e16888aa1b0a011; 19913b4eac4a230dccb548931358398f45dabe4c before 61d9f27b191b838b96b697ce0bfaee39a138243a; 19913b4eac4a230dccb548931358398f45dabe4c before 06fb5e623cdc2402d6bb29be94d9beb9a826ffec; 19913b4eac4a230dccb548931358398f45dabe4c before e7c2fd3893a7f7fcd7e8cf0b2c6348bb1e893df6; 19913b4eac4a230dccb548931358398f45dabe4c before eff8013c5a8916613c742ae5a2cc341cb605c0ae; 3.15 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-89652
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-89652
git.kernel.org
https://git.kernel.org/stable/c/06fb5e623cdc2402d6bb29be94d9beb9a826ffec
git.kernel.org
https://git.kernel.org/stable/c/61d9f27b191b838b96b697ce0bfaee39a138243a
git.kernel.org
https://git.kernel.org/stable/c/a294064e0e0f81ea607b2f019e16888aa1b0a011
git.kernel.org
https://git.kernel.org/stable/c/e7c2fd3893a7f7fcd7e8cf0b2c6348bb1e893df6
git.kernel.org
https://git.kernel.org/stable/c/eff8013c5a8916613c742ae5a2cc341cb605c0ae
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