CVE-2026-89652: Linux kernel · ceph: bound copied dentry name length in NFS export get_name
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 9.8 Critical.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 39% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 11 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available that adds proper length checks before copying the dentry name to prevent buffer overflow. Systems running affected linux-aws kernel versions should update to a patched kernel version that includes ceph_export_copy_name() and related fixes. No additional mitigations are specified beyond applying the official patch.
Description
A vulnerability in the Linux kernel's Ceph filesystem integration allows a malicious or compromised Ceph Metadata Server (MDS) to cause a buffer overflow in the NFS export get_name path. This occurs because the dentry name length is not properly checked against the maximum allowed size (NAME_MAX) before copying, leading to an out-of-bounds write. The issue affects specific linux-aws kernel versions and is exploitable when a CephFS mount is re-exported over NFS. A fix has been implemented by adding length checks to prevent overflow.
References
- nvd.nist.gov/vuln/detail/CVE-2026-89652 (opens in a new tab)
- git.kernel.org/stable/c/06fb5e623cdc2402d6bb29be94d9beb9a826ffec (opens in a new tab)
- git.kernel.org/stable/c/61d9f27b191b838b96b697ce0bfaee39a138243a (opens in a new tab)
- git.kernel.org/stable/c/e7c2fd3893a7f7fcd7e8cf0b2c6348bb1e893df6 (opens in a new tab)
- git.kernel.org/stable/c/eff8013c5a8916613c742ae5a2cc341cb605c0ae (opens in a new tab)
- ubuntu.com/security/CVE-2026-89652 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89652 (opens in a new tab)
- git.kernel.org/linus/eff8013c5a8916613c742ae5a2cc341cb605c0ae (opens in a new tab)