Vulnerability in Gnome Yelp

CVE-2026-13601

A flaw was found in Yelp due to an overly permissive Content Security Policy (CSP) implementation provided by yelp-xsl. A malicious Flatpak application can open crafted help content through the OpenURI portal. By embedding an untrusted CSS stylesheet within a structured SVG document, attacker-controlled content can bypass Flatpak's intended sandbox isolation, allowing Yelp to evaluate local XML inclusions and disclose arbitrary user-readable host files through remote CSS resource requests. This may result in the unauthorized disclosure of sensitive information.

EPSS: 0.001 (2.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-13601?
CVE-2026-13601 is a high-severity vulnerability in Gnome Yelp, classified under Protection Mechanism Failure. CVSS score: 7.1/10. Published 2026-06-29.
How severe is CVE-2026-13601?
High severity. CVSS v3 base score is 7.1 out of 10.