Mozilla Firefox up to 140 memory corruption

Summaryinfo

A vulnerability has been found in Mozilla Firefox up to 140 and classified as critical. This affects an unknown part. This manipulation causes memory corruption. This vulnerability is handled as CVE-2025-8040. The attack can be initiated remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as critical was found in Mozilla Firefox up to 140. Affected by this vulnerability is an unknown part. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

Memory safety bugs present in Firefox ESR 140.0, Thunderbird ESR 140.0, Firefox 140 and Thunderbird 140. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 141, Firefox ESR < 140.1, Thunderbird < 141, and Thunderbird < 140.1.

The advisory is shared at bugzilla.mozilla.org. This vulnerability is known as CVE-2025-8040 since 07/22/2025. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 08/09/2025).

The vulnerability scanner Nessus provides a plugin with the ID 242558 (Mozilla Firefox ESR < 140.1), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 141 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (242558), EUVD (EUVD-2025-22360) and CERT Bund (WID-SEC-2025-1623). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Fedora Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• IGEL OS
• Mozilla Firefox
• Mozilla Firefox ESR
• Mozilla Thunderbird

Productinfo

Type

• Web Browser

Vendor

• Mozilla

Name

• Firefox

Version

• 140

License

• open-source

Website

• Vendor: https://www.mozilla.org/
• Product: https://www.mozilla.org/en-US/firefox/

CPE 2.3info

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CPE 2.2info

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If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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