CVE-2026-43359: Linux kernel · btrfs: fix transaction abort on set received ioctl due to item overflow
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium · fixed in 6.8.0-1061.64~22.04.1 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 6.8.0-1061.64~22.04.1, 6.8.0-1063.71~22.04.1, 6.8.0-1062.69~22.04.1 +30
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 8 May 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
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde@7.0.0-1008.8?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 25.10linuxpkg:deb/ubuntu/linux?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=questingOther 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 is available that fixes this vulnerability by adding an early item overflow check before starting the transaction. Users should apply the official Linux kernel updates that address this issue. No additional mitigation is required as the vulnerability is fixed in the updated kernel versions.
Description
A vulnerability in the Linux kernel's Btrfs filesystem allows a local user owning a subvolume to cause a transaction abort and force the filesystem into read-only mode by triggering an item overflow in the set received ioctl operation. This occurs because the ioctl does not require administrative privileges and the kernel did not check for overflow before starting a transaction. The issue has been fixed by adding an early overflow check before transaction initiation.
References
- ubuntu.com/security/CVE-2026-43359 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-43359 (opens in a new tab)
- git.kernel.org/linus/87f2c46003fce4d739138aab4af1942b1afdadac (opens in a new tab)
- git.kernel.org/stable/c/2e57b8cac2ba0d38aac76c1ecdfd8b899e3581a5 (opens in a new tab)
- git.kernel.org/stable/c/41fb97353ff58fa4f31904c343fc8e3df2f7517d (opens in a new tab)
- git.kernel.org/stable/c/87f2c46003fce4d739138aab4af1942b1afdadac (opens in a new tab)
- git.kernel.org/stable/c/b19c0465e4daad5aa8f60552ea0578cf31a11b1e (opens in a new tab)
- git.kernel.org/stable/c/b9914db13ac15aca3b74544c0bb1a2e0dad1f174 (opens in a new tab)
- git.kernel.org/stable/c/d11aefe654a04fc41996d254748d6a38b6b0a7be (opens in a new tab)
- ubuntu.com/security/notices/USN-8567-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8574-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8574-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8595-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8596-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8595-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8606-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8607-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8608-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8609-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8574-3 (opens in a new tab)