Description
Use-after-free in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
Published: 2026-10-27
Score: n/a
EPSS: n/a
KEV: No
Impact: Memory corruption that may lead to arbitrary code execution
Action: Apply Patch
AI Analysis

Impact

The flaw is a use‑after‑free bug in the Layout: Text and Fonts component of Firefox. When triggered by crafted content, the browser accesses freed memory, which can lead to a crash, denial of service, or potentially arbitrary code execution. The vulnerability directly compromises the integrity and reliability of the rendering engine.

Affected Systems

Mozilla’s Firefox browser and Mozilla Thunderbird are affected. Versions released before Firefox 159 and Firefox ESR 153.6, and before Thunderbird 159 and Thunderbird 153.6 contain the unpatched code. Users on those releases are vulnerable until they update to the patched releases.

Risk and Exploitability

The EPSS score is not available and the vulnerability is not listed in CISA’s KEV catalog, indicating no publicly confirmed exploits to date. Nonetheless, a memory corruption flaw can be leveraged by an attacker who can supply malicious text or font data, such as via a crafted web page or document processed by the browser. The attack vector is likely remote, delivered over the network, and may require the user to view or interact with the malicious content.

Generated by OpenCVE AI on October 27, 2026 at 21:57 UTC.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Upgrade Firefox to version 159 or later, or to ESR 153.6 or later, to obtain the fixed layout engine.
  • Where an upgrade is not immediately feasible, limit the browser’s exposure to untrusted text and font content by disabling or restricting features that render complex layouts, or by running the browser under a sandbox that isolates the rendering process.
  • Deploy policy controls that block or quarantine SVG, web fonts, or other complex font rendering on untrusted sites until the browser can be updated to the patched version.

Generated by OpenCVE AI on October 27, 2026 at 21:57 UTC.

Tracking

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Advisories

No advisories yet.

History

Tue, 27 Oct 2026 22:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-416

Tue, 27 Oct 2026 21:00:00 +0000

Type Values Removed Values Added
First Time appeared Mozilla
Mozilla firefox
Mozilla thunderbird
Vendors & Products Mozilla
Mozilla firefox
Mozilla thunderbird

Tue, 27 Oct 2026 18:45:00 +0000

Type Values Removed Values Added
Description Use-after-free in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox 159, Firefox ESR 153.6, and Thunderbird 159. Use-after-free in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
References

Tue, 27 Oct 2026 18:30:00 +0000

Type Values Removed Values Added
Description Use-after-free in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox 159 and Firefox ESR 153.6. Use-after-free in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox 159, Firefox ESR 153.6, and Thunderbird 159.
References

Tue, 27 Oct 2026 16:00:00 +0000

Type Values Removed Values Added
Weaknesses CWE-416

Tue, 27 Oct 2026 14:15:00 +0000

Type Values Removed Values Added
Description Use-after-free in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox 159 and Firefox ESR 153.6.
Title Use-after-free in the Layout: Text and Fonts component
References

Subscriptions

Mozilla Firefox Thunderbird
cve-icon MITRE

Status: PUBLISHED

Assigner: mozilla

Published:

Updated: 2026-10-27T18:28:40.228Z

Reserved: 2026-10-27T14:05:17.732Z

Link: CVE-2026-117902

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Deferred

Published: 2026-10-27T14:16:45.643

Modified: 2026-10-27T19:17:15.460

Link: CVE-2026-117902

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-27T22:00:17Z

Weaknesses

No weakness.