Vulnerability · Published Oct 14, 2025 · Assigned by mozilla

CVE-2025-11711Some non-writable Object properties could be modified

Medium 6.5

In plain English

A medium-severity security flaw in Firefox from Mozilla. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 14% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)6.5Medium
Exploit odds (30 days)0.2%top 86.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

There was a way to change the value of JavaScript Object properties that were supposed to be non-writeable. This vulnerability was fixed in Firefox 144, Firefox ESR 115.29, Firefox ESR 140.4, Thunderbird 144, and Thunderbird 140.4.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:10firefox140.4.0-3.el10_0ALSA-2025:18154
AlmaLinux:8firefox140.4.0-3.el8_10.alma.1ALSA-2025:18285
AlmaLinux:9firefox140.4.0-3.el9_6.alma.1ALSA-2025:18155
AlmaLinux:9firefox-x11140.4.0-3.el9_6.alma.1ALSA-2025:18155
AlmaLinux:10thunderbird140.4.0-2.el10_0.alma.1ALSA-2025:18320
AlmaLinux:8thunderbird140.4.0-2.el8_10.alma.1ALSA-2025:18983
AlmaLinux:9thunderbird140.4.0-2.el9_6.alma.1ALSA-2025:18321
Debian:12firefox-esr140.4.0esr-1~deb12u1DSA-6025-1
Debian:12firefox-esr140.4.0esr-1~deb12u1DEBIAN-CVE-2025-11711
Debian:13firefox-esr140.4.0esr-1~deb13u1DEBIAN-CVE-2025-11711
Debian:13firefox-esr140.4.0esr-1~deb13u1DSA-6025-1
Debian:14firefox-esr140.4.0esr-1DEBIAN-CVE-2025-11711
Debian:12thunderbird1:140.4.0esr-1~deb12u1DSA-6040-1
Debian:12thunderbird1:140.4.0esr-1~deb12u1DEBIAN-CVE-2025-11711
Debian:13thunderbird1:140.4.0esr-1~deb13u1DSA-6040-1
Debian:13thunderbird1:140.4.0esr-1~deb13u1DEBIAN-CVE-2025-11711
Debian:14thunderbird1:140.4.0esr-1DEBIAN-CVE-2025-11711
Rocky Linux:10firefox0:140.4.0-3.el10_0RLSA-2025:18154
Rocky Linux:8firefox0:140.4.0-3.el8_10RLSA-2025:18285
Rocky Linux:9firefox0:140.4.0-3.el9_6RLSA-2025:18155
Rocky Linux:10thunderbird0:140.4.0-2.el10_0RLSA-2025:18320
Rocky Linux:8thunderbird0:140.4.0-2.el8_10RLSA-2025:18983
Rocky Linux:9thunderbird0:140.4.0-2.el9_6RLSA-2025:18321
Ubuntu:22.04:LTSmozjs102no fix listedUBUNTU-CVE-2025-11711
Ubuntu:24.04:LTSmozjs102no fix listedUBUNTU-CVE-2025-11711
Ubuntu:24.04:LTSmozjs115no fix listedUBUNTU-CVE-2025-11711
Ubuntu:22.04:LTSmozjs78no fix listedUBUNTU-CVE-2025-11711
Ubuntu:22.04:LTSmozjs91no fix listedUBUNTU-CVE-2025-11711
Ubuntu:22.04:LTSthunderbird1:140.7.1+build1-0ubuntu0.22.04.1UBUNTU-CVE-2025-11711

Affected products (as reported)

VendorProductVersions
Mozilla Firefox see references
Mozilla Thunderbird see references

Weakness: CWE-591 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

References