SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2025-26596

A heap overflow flaw was found in X.Org and Xwayland.

HIGH 7.8EPSS 0.43%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.43%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A heap overflow flaw was found in X.Org and Xwayland. The computation of the length in XkbSizeKeySyms() differs from what is written in XkbWriteKeySyms(), which may lead to a heap-based buffer overflow.

CVSS 3.1
7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
0.43% probability · 36th percentile
CISA KEV
Not listed
Weakness
CWE-787
Affected
tigervnc/tigervnc · x.org/x server · x.org/xwayland · redhat/enterprise linux
Source
secalert@redhat.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.