CVE-2026-97521: Linux kernel · gfs2: fix quota init duplicate scan
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 26 Oct 2026, 12:55 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 4% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Exploitation evidence
Disclosed: evidence found.
CVE published 24 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 patch fixing this issue has been applied to the affected Linux kernel versions. Users should update to the fixed kernel versions listed by their distribution or vendor. Since this is a kernel-level fix, applying the official kernel updates is the recommended remediation. No additional mitigations are indicated.
Description
A vulnerability in the Linux kernel's gfs2 quota initialization was fixed. The issue involved the gfs2_quota_init() function checking for duplicate quota_change IDs while holding locks that should not allow sleeping. On PREEMPT_RT kernels, the locking mechanism could cause a sleeping function call in an invalid context, leading to potential kernel stability issues. The fix refactors the locking and lookup logic to prevent sleeping under the bucket bitlock. This bug was reported by syzbot and affects specific Linux kernel versions.
References
- ubuntu.com/security/CVE-2026-97521 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-97521 (opens in a new tab)
- git.kernel.org/stable/c/7fdcf16e5e14e11028f5bcaa6d25075eb5e876a0 (opens in a new tab)
- git.kernel.org/stable/c/812a766e2b0a8f4d094393fad13475c57f5f86db (opens in a new tab)
- git.kernel.org/stable/c/b99a1f0f18ee50445907f55069e88bcfd8947383 (opens in a new tab)