1. Ubuntu Security Notices
  2. USN-7191-1

USN-7191-1: Firefox vulnerabilities

Publication date

9 January 2025

Overview

Several security issues were fixed in Firefox.

Releases

Packages

  • firefox - Mozilla Open Source web browser

Details

Multiple security issues were discovered in Firefox. If a user were
tricked into opening a specially crafted website, an attacker could
potentially exploit these to cause a denial of service, obtain sensitive
information across domains, or execute arbitrary code. (CVE-2025-0237,
CVE-2025-0239, CVE-2025-0240, CVE-2025-0242, CVE-2025-0243, CVE-2025-0247)

Irvan Kurniawan discovered that Firefox incorrectly handled memory when
breaking lines in text, leading to a use-after-free vulnerability. An
attacker could possibly use this issue to cause a denial of service or
possibly execute arbitrary code. (CVE-2025-0238)

Nils Bars discovered that Firefox incorrectly handled memory when...

Multiple security issues were discovered in Firefox. If a user were
tricked into opening a specially crafted website, an attacker could
potentially exploit these to cause a denial of service, obtain sensitive
information across domains, or execute arbitrary code. (CVE-2025-0237,
CVE-2025-0239, CVE-2025-0240, CVE-2025-0242, CVE-2025-0243, CVE-2025-0247)

Irvan Kurniawan discovered that Firefox incorrectly handled memory when
breaking lines in text, leading to a use-after-free vulnerability. An
attacker could possibly use this issue to cause a denial of service or
possibly execute arbitrary code. (CVE-2025-0238)

Nils Bars discovered that Firefox incorrectly handled memory when using
JavaScript Text Segmentation. An attacker could possibly use this issue to
cause a denial of service. (CVE-2025-0241)

Update instructions

After a standard system update you need to restart Firefox to make all the necessary changes.

Learn more about how to get the fixes.

The problem can be corrected by updating your system to the following package versions:

Ubuntu Release Package Version
20.04 focal firefox –  134.0+build1-0ubuntu0.20.04.1

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References

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