CVE-2025-26597: xserver · Memory Buffer Overflow
Affects xserverSource GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 5 Nov 2026, 00:01 UTC
Thin evidence
One scorer or none| CNA (redhat) | CVSS 3.1 | 7.8 |
|---|
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 38% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 25 Feb 2025
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 5 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| xserver | Affected
| Fixed in– |
AI-suggested
A security update addressing this vulnerability is available. Users should apply the official patches provided by their vendor. For Red Hat Enterprise Linux 9 and related distributions, updated packages have been released as per Red Hat Advisory RHSA-2025:2500. Applying these updates will remediate the buffer overflow issue. No additional mitigation steps are required beyond applying the vendor-provided fix.
Description
CVE-2025-26597 is a buffer overflow vulnerability in the X.Org xserver and Xwayland components. The flaw occurs when the function XkbChangeTypesOfKey() is called with a zero group value, causing the key symbols table to resize to zero while leaving key actions unchanged. Subsequent calls with a non-zero group value lead to a buffer overflow due to mismatched sizes between key symbols and key actions.
References
- access.redhat.com/errata/RHSA-2025:2500 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:2502 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:2861 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:2862 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:2865 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:2866 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:2873 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:2874 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:2875 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:2879 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:2880 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:3976 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:7163 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:7165 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:7458 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2025-26597 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2345255 (opens in a new tab)
- lists.debian.org/debian-lts-announce/2025/02/msg00036.html (opens in a new tab)
- openwall.com/lists/oss-security/2026/06/02/1 (opens in a new tab)