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Fencer Vulns
medium 6.3

CVE-2023-40791 json

extract_user_to_sg in lib/scatterlist.c in the Linux kernel before 6.4.12 fails to unpin pages in a certain situation, as demonstrated by a…

published 2023-10-16 3 y ago modified 2026-06-17 4 mo ago also EUVD-2023-45342

cvss
6.3
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 41%
public exploits
0
none known

Summary

extract_user_to_sg in lib/scatterlist.c in the Linux kernel before 6.4.12 fails to unpin pages in a certain situation, as demonstrated by a WARNING for try_grab_page.

Patch / fix

  • linux linux_kernel 6.4.12
  • linux Debian 14, Debian 13 6.4.13-1

debian advisories DEBIAN-CVE-2023-40791

  • kernel CBL-Mariner 2.0 5.15.135.1-2

azure linux advisories AZL-31564

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2023-40791 updated cvss 6.3

kernel: lib/scatterlist.c fails to unpin pages

  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +82 more
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.48% chance of exploitation in the next 30 days, higher than 41% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • lkml.org https://lkml.org/lkml/2023/8/3/323 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 6.3 CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H

Classification

Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.