[UPDATE] [medium] X.Org X11: Multiple vulnerabilities allow unspecified effects, possibly code execution

CSIRTS triage

What

A local attacker can exploit multiple vulnerabilities in X.Org X11 to cause unspecified effects, which may lead to the execution of arbitrary code.

Who is affected

Local users of X.Org X11.

Urgency

Remediation is important due to the potential for arbitrary code execution.

Action

Update to the latest version of X.Org X11.

AI-assisted analysis generated from the source advisory — verify against the original.

Details

Source

CERT-Bund (BSI) Security Advisories (DE · national-cert · site)

Severity

medium

Published

2026-08-26

Exploitation

Not in CISA KEV at last sync

Language

Machine-translated to English — verify against the original

Original advisory: https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2025-0435

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

• Low exploitation riskCVE-2025-265940.39% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 32% of all EPSS-scored CVEs.
• Low exploitation riskCVE-2025-265950.43% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 36% of all EPSS-scored CVEs.
• Low exploitation riskCVE-2025-265960.43% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 36% of all EPSS-scored CVEs.
• Low exploitation riskCVE-2025-265970.43% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 37% of all EPSS-scored CVEs.
• Low exploitation riskCVE-2025-265980.40% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 33% of all EPSS-scored CVEs.
• Low exploitation riskCVE-2025-265990.40% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 33% of all EPSS-scored CVEs.
• Low exploitation riskCVE-2025-266000.39% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 32% of all EPSS-scored CVEs.
• Low exploitation riskCVE-2025-266010.39% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 32% of all EPSS-scored CVEs.

Referenced CVEs

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

• high[NEW] [high] Oracle Solaris third-party components: Multiple vulnerabilitiescert-bund

Recent advisories for X.Org X11

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

• medium[UPDATE] [mittel] X.Org X11 (libXfont2): Mehrere Schwachstellen ermöglichen Privilegieneskalation und Denial o…cert-bund · 2026-09-10
• high[NEW] [high] X.Org X11 and Xwayland: Multiple vulnerabilities allow code execution and DoScert-bund · 2026-09-02
• medium[UPDATE] [medium] X.Org X11, Xwayland: Multiple vulnerabilitiescert-bund · 2026-08-26
• high[UPDATE] [high] Xwayland and X.Org X11: Multiple vulnerabilities allow unspecified attackcert-bund · 2026-08-26
• medium[UPDATE] [medium] X.Org X11 and Xwayland: Multiple vulnerabilitiescert-bund · 2026-08-26
• medium[UPDATE] [medium] X.Org X11 and Xwayland: Multiple vulnerabilitiescert-bund · 2026-08-26

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