CVE-2026-109723

5.4Medium

Published 13 Oct 2026 · NVD status: Deferred · AI triage by gemini-3.8-flash

5.4Medium

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: Required
Impact: Limited impact
Weakness: CWE-190

Impact

Attackers can achieve limited unauthorized data access or modification if a user visits a malicious page or views a crafted email. Exploitation requires user interaction to render untrusted text or fonts.

Root cause

An integer overflow occurs when processing text and fonts in the layout engine.

Affected systems

Firefox prior to 158, Firefox ESR prior to 153.5, Thunderbird prior to 158, and Thunderbird prior to 153.5.

CVSS v3.1 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

Fix & remediation

Upgrade to Firefox 158, Firefox ESR 153.5, Thunderbird 158, or Thunderbird 153.5; no interim workarounds are provided.

shell

$ sudo apt-get update && sudo apt-get install --only-upgrade firefox thunderbird

AI-suggested. Run it in staging first and check it against the vendor advisory. Why?

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NVD description

Integer overflow in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.

References

Source: nvd.nist.gov/vuln/detail/CVE-2026-109723