CVE-2026-72068: Linux kernel · posix-cpu-timers: Use u64 multiplication in update_rlimit_cpu()
Affects Linux kernelSource GCVE Database
Not known to be exploited · fixed in 5.15.0-1117.124~20.04.1 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 14:05 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 12% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1117.124~20.04.1, 5.15.0-1123.132~20.04.1, 5.15.0-1122.131~20.04.1 +41
Exploitation evidence
Disclosed: evidence found.
CVE published 15 Aug 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 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 is available and should be applied to affected Linux Azure kernel versions to correct the 64-bit multiplication in update_rlimit_cpu(). Applying the official fix resolves the premature timer expiry issue. No additional mitigation is required beyond updating to a fixed kernel version.
Description
A vulnerability in the Linux kernel's posix-cpu-timers subsystem caused incorrect CPU timer expiry programming on 32-bit kernels due to improper 64-bit multiplication handling in update_rlimit_cpu(). This led to premature firing of process CPU timers for RLIMIT_CPU soft limits of 5 seconds or more. The enforcement of CPU time limits remains correct, but the expiry cache programming was flawed. The issue does not affect 64-bit kernels and has been fixed in affected Linux Azure kernel versions.
References
- nvd.nist.gov/vuln/detail/CVE-2026-72068 (opens in a new tab)
- git.kernel.org/stable/c/1fafc4d9b411645eb34de43362b966dc8fb3e263 (opens in a new tab)
- git.kernel.org/stable/c/26aff38fefb1d6cd87e22525f41cc8f1aa61b24f (opens in a new tab)
- git.kernel.org/stable/c/384628d6cdde0fcd76868606fad3ad8293100afb (opens in a new tab)
- git.kernel.org/stable/c/571e1f10b5996ba3e4dc63ea77de4aa309c384ce (opens in a new tab)
- git.kernel.org/stable/c/cff8281bacd2866767e6194c3079d33b6c5a74f4 (opens in a new tab)
- git.kernel.org/stable/c/ea6a188ee805e841a0e242f14d15953e0dfa74bb (opens in a new tab)
- git.kernel.org/stable/c/edf6babb9edd2d3e19229ade339081f439d4f478 (opens in a new tab)
- git.kernel.org/stable/c/feb5c87c8514444ba891b75a5a3eae57c64edaf8 (opens in a new tab)
- ubuntu.com/security/CVE-2026-72068 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-72068 (opens in a new tab)
- git.kernel.org/linus/26aff38fefb1d6cd87e22525f41cc8f1aa61b24f (opens in a new tab)
- ubuntu.com/security/notices/USN-8876-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8878-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8879-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8877-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8875-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8889-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-2 (opens in a new tab)