CVE-2025-11712 Affecting firefox-esr package, versions <140.4.0esr-1


Severity

Recommended
low

Based on default assessment until relevant scores are available.

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  • Snyk IDSNYK-DEBIANUNSTABLE-FIREFOXESR-13550648
  • published15 Oct 2025
  • disclosed14 Oct 2025

Introduced: 14 Oct 2025

NewCVE-2025-11712  (opens in a new tab)

How to fix?

Upgrade Debian:unstable firefox-esr to version 140.4.0esr-1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream firefox-esr package and not the firefox-esr package as distributed by Debian. See How to fix? for Debian:unstable relevant fixed versions and status.

A malicious page could have used the type attribute of an OBJECT tag to override the default browser behavior when encountering a web resource served without a content-type. This could have contributed to an XSS on a site that unsafely serves files without a content-type header. This vulnerability affects Firefox < 144, Firefox ESR < 140.4, Thunderbird < 144, and Thunderbird < 140.4.

CVSS Base Scores

version 3.1