CVE-2026-23233: Linux kernel · f2fs: fix to avoid mapping wrong physical block for swapfile
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 6.8.0-1060.63~22.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 5% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 6.8.0-1060.63~22.04.1, 6.8.0-1063.69~22.04.1, 6.8.0-1060.61~22.04.1 +24
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 4 Mar 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 25.10linuxpkg:deb/ubuntu/linux@6.17.0-40.40?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws@6.17.0-1019.19?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure@6.17.0-1020.20?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde@6.17.0-1017.17?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-gcppkg:deb/ubuntu/linux-gcp@6.17.0-1020.22?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-oraclepkg:deb/ubuntu/linux-oracle@6.17.0-1018.18?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
An official fix is available and included in updated Linux kernel releases. Users should apply the vendor-provided kernel updates to resolve this issue. The Ubuntu advisory USN-8492-1 confirms that this and other kernel vulnerabilities have been addressed. No additional mitigation steps are required beyond applying the official patch.
Description
A vulnerability in the Linux kernel's F2FS filesystem was fixed to prevent incorrect mapping of physical blocks for swapfiles. The issue occurs when a small swapfile (< 2MB) with a fragmented physical layout is used on kernel versions 6.6 and later, causing data corruption and potential system instability. The root cause was improper handling of unaligned swapfile extents in the check_swap_activate() function, leading to overwriting of unrelated data. This flaw was resolved by ensuring correct block mapping after migrating all blocks in the swapfile tail.
References
- ubuntu.com/security/CVE-2026-23233 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-23233 (opens in a new tab)
- git.kernel.org/linus/5c145c03188bc9ba1c29e0bc4d527a5978fc47f9 (opens in a new tab)
- git.kernel.org/stable/c/1ff415eef513bf12deb058fc50d57788c46c48e6 (opens in a new tab)
- git.kernel.org/stable/c/5c145c03188bc9ba1c29e0bc4d527a5978fc47f9 (opens in a new tab)
- git.kernel.org/stable/c/607cb9d83838d2cd9f0406c2403ed61aadf0edff (opens in a new tab)
- git.kernel.org/stable/c/d4534a7f6c92baaf7e12a45fc6e37332cafafc33 (opens in a new tab)
- git.kernel.org/stable/c/fee27b69dde1a05908b350eea42937af2387c4fe (opens in a new tab)
- ubuntu.com/security/notices/USN-8492-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8492-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8497-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8498-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8499-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8492-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8492-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8492-5 (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-8609-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8619-1 (opens in a new tab)