GHSA-F4VH-QR53-Q5GV

Vulnerability from github – Published: 2026-06-29 12:31 – Updated: 2026-08-20 12:31
VLAI
Details

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.

Severity
7.1 (High)
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
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{
  "affected": [],
  "aliases": [
    "CVE-2026-13601"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-693"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-29T10:16:30Z",
    "severity": "HIGH"
  },
  "details": "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\u0027s 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.",
  "id": "GHSA-f4vh-qr53-q5gv",
  "modified": "2026-08-20T12:31:20Z",
  "published": "2026-06-29T12:31:44Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-13601"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:47177"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:47178"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:54539"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:54540"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:54605"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:54624"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:54637"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:54666"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:57417"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-13601"
    },
    {
      "type": "WEB",
      "url": "https://blogs.gnome.org/mcatanzaro/2026/05/11/flatpak-sandbox-escape-via-yelp"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2494110"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.gnome.org/GNOME/yelp/-/commit/c8c8244c8a812860782d635890c9b6c43ecc2639"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.gnome.org/GNOME/yelp/-/work_items/238"
    },
    {
      "type": "WEB",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-13601.json"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}



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