CVE-2026-99124: Linux kernel · s390/pci: Fix leak of uninitialized kernel data in SCLP report
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 29 Oct 2026, 22:35 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
Thin evidence
One scorer or noneExploitation evidence
Disclosed: evidence found.
CVE published 28 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 29 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.
Description
In the Linux kernel, the following vulnerability has been resolved: s390/pci: Fix leak of uninitialized kernel data in SCLP report While report_error_write() checks that the provided buffer is at least as large as the header struct, but not that it is large enough to contain the report with the length claimed by report->length. If user-space provides a short buffer, meaning a larger report->length than the actually written payload, up to around 4K of kernel data from past the kmalloc(len + 1) sized buffer allocated in kernfs_fop_write_iter() will leak into the SCLP report. However, as the entity processing the SCLP is privileged and able to access at least the page including the report, this does not leak data that entity could not access but it is still an out of bounds read and a malformed error report that should be rejected.
References
- ubuntu.com/security/CVE-2026-99124 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-99124 (opens in a new tab)
- git.kernel.org/stable/c/8ac60ae2a307a50b599bf5d300b448d638f3ba29 (opens in a new tab)
- git.kernel.org/stable/c/ba5001db9bb23ff7d2ea328c405c287ffb07786f (opens in a new tab)
- git.kernel.org/stable/c/126a7c227d8543e13903dd5622640c1f0fcc5a16 (opens in a new tab)