Unscored severity · published Oct 28, 2026
CVE-2026-99124
s390/pci: Fix leak of uninitialized kernel data in SCLP report
New
–
CVSS
–
EPSS
No
On KEV
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.
Exploitation
Is it being used?
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Linux · Linux
368704a65be8620df795ccbeb44e025dafbc3e1f before ba5001db9bb23ff7d2ea328c405c287ffb07786f; 368704a65be8620df795ccbeb44e025dafbc3e1f before 126a7c227d8543e13903dd5622640c1f0fcc5a16; 368704a65be8620df795ccbeb44e025dafbc3e1f before 8ac60ae2a307a50b599bf5d300b448d638f3ba29; 4.7 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-99124
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-99124
git.kernel.org
https://git.kernel.org/stable/c/ba5001db9bb23ff7d2ea328c405c287ffb07786f
git.kernel.org
https://git.kernel.org/stable/c/126a7c227d8543e13903dd5622640c1f0fcc5a16
git.kernel.org
https://git.kernel.org/stable/c/8ac60ae2a307a50b599bf5d300b448d638f3ba29
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