CVE-2026-89525: Linux kernel · udf: reject VAT indexes equal to the entry count
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 26 Oct 2026, 17:16 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 7% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Exploitation 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 corrects the bounds check in udf_get_pblock_virt15() to reject indexes greater than or equal to s_num_entries. Users should apply the official Linux kernel patches that address this issue. Since this is a kernel-level vulnerability, updating to a patched kernel version is the recommended remediation. No vendor advisory content was provided, so check the Linux kernel or distribution vendor advisories for the specific patch details and apply them accordingly.
Description
A vulnerability in the Linux kernel's UDF filesystem implementation allows an out-of-bounds read due to improper bounds checking of VAT indexes. The issue arises because the code incorrectly permits an index equal to the number of entries, leading to a read past the allocated VAT table. This can cause a kernel panic or memory corruption. The flaw affects specific Linux kernel versions listed and was demonstrated with a reproducer causing a KASAN slab-out-of-bounds error.
References
- nvd.nist.gov/vuln/detail/CVE-2026-89525 (opens in a new tab)
- git.kernel.org/stable/c/1bd7947f1463c21edafa256d0fbec5b99215e2b6 (opens in a new tab)
- git.kernel.org/stable/c/9193368408d792cec2057628d87862140fb1ce1c (opens in a new tab)
- git.kernel.org/stable/c/b95c33a4e743874f1b0a45bf2aaa4da553552bd1 (opens in a new tab)
- git.kernel.org/stable/c/cac0cb07f29ccfb373fd4a36c81e908ef3ce608c (opens in a new tab)
- ubuntu.com/security/CVE-2026-89525 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89525 (opens in a new tab)
- git.kernel.org/linus/cac0cb07f29ccfb373fd4a36c81e908ef3ce608c (opens in a new tab)