CVE-2026-72025: Linux kernel · s390/monwriter: Reject buffer reuse with different data length
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 11% 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
An official fix is available and should be applied to affected Linux kernel versions. The fix adds validation to reject buffer reuse with different data lengths, preventing out-of-bounds memory access. Systems using affected kernel versions should update to patched releases as provided by their vendor.
Description
A vulnerability in the Linux kernel's s390 monwriter misc device allowed reuse of data buffers with different data lengths without proper validation. This flaw could lead to out-of-bounds user copy to the kernel buffer and memory corruption. The monwriter device is created with root-only permissions by default, limiting practical impact. The issue has been fixed by adding checks to reject records with changed data lengths.
References
- nvd.nist.gov/vuln/detail/CVE-2026-72025 (opens in a new tab)
- git.kernel.org/stable/c/01f3ce411711c2c919598ea25320a5a48f71edbc (opens in a new tab)
- git.kernel.org/stable/c/036bc5661060702e798d215e81bb46da530965b3 (opens in a new tab)
- git.kernel.org/stable/c/096dff1247037d329c04b3a5be0ecdfb1c5c7ac6 (opens in a new tab)
- git.kernel.org/stable/c/2995ccec260caa9e85b3301a4aba1e66ed80ad74 (opens in a new tab)
- git.kernel.org/stable/c/759d91378203ea35fa9bca6726dcf0010de081fb (opens in a new tab)
- git.kernel.org/stable/c/ae5347f3db1782c6118f6cc0d9fd8b1d43397db3 (opens in a new tab)
- git.kernel.org/stable/c/d39cf4a6d721b1ae21eb53bbf3e8cd984253d7ab (opens in a new tab)
- git.kernel.org/stable/c/f0745496f7c171271cafd9457df3b914a483ddeb (opens in a new tab)
- ubuntu.com/security/CVE-2026-72025 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-72025 (opens in a new tab)
- git.kernel.org/linus/2995ccec260caa9e85b3301a4aba1e66ed80ad74 (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)