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Fencer Intel
medium 6.9

CVE-2026-109904 json

X.Org Server XRes QueryClientIds Request Size Overflow

published 2d ago modified yesterday also EUVD-2026-125273

cvss
6.9
version 4.0, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 5%
public exploits
0
none known

Summary

A buffer overread caused by an integer-overflow in Proc/SProcXResQueryClientIds in X.Org xwayland before 24.1.15 and X Server before 21.1.26 could be used by attackers on authenticated X clients to crash the server or leak out information.

Patch / fix

  • X.Org xorg-x11-server 21.1.26
  • X.Org xwayland 24.1.15
  • xorg-x11-server SLE High Performance Computing 15 SP4-ESPOS, SLES for SAP 15 SP4, SLES 15 SP4-LTSS +1 more 1.20.3-150400.38.80.1
  • xorg-x11-server SLES LTSS Extended Security 12 SP5, SLES 12 SP5-LTSS 1.19.6-10.117.1

suse advisories SUSE-SU-2026:5180-1SUSE-SU-2026:5178-1

  • xorg-x11-server openSUSE Leap 16.0 21.1.15-160000.7.1
  • xorg-x11-server openSUSE Tumbleweed 21.1.25-2.1
  • xwayland openSUSE Tumbleweed 24.1.14-2.1

opensuse advisories openSUSE-SU-2026:22274-1openSUSE-SU-2026:12534-1openSUSE-SU-2026:12535-1

  • xwayland Alpine 3.24 24.1.15-r0
  • xorg-server Alpine 3.24 21.1.26-r0

alpine advisories ALPINE-CVE-2026-109904

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

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Exploit prediction

0.16% chance of exploitation in the next 30 days, higher than 5% of all scored CVEs (FIRST EPSS, 2026-11-14).

CVSS scores

assigned by version score vector
CNA 4.0 6.9 CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N
CNA 4.0 6.9 CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

  • X.Org xorg-x11-server
  • X.Org xwayland

Classification

Weakness

References

Sources

Fencer Intel 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.