Mozilla Thunderbird up to 143 WebGL Texture out-of-bounds write

Summaryinfo

A vulnerability was found in Mozilla Thunderbird up to 143. It has been classified as critical. The affected element is an unknown function of the component WebGL Texture Handler. The manipulation leads to out-of-bounds write. This vulnerability is referenced as CVE-2025-11709. Remote exploitation of the attack is possible. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Mozilla Thunderbird up to 143 and classified as critical. This issue affects an unknown code block of the component WebGL Texture Handler. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. Using CWE to declare the problem leads to CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

A compromised web process was able to trigger out of bounds reads and writes in a more privileged process using manipulated WebGL textures. This vulnerability affects Firefox < 144, Firefox ESR < 115.29, Firefox ESR < 140.4, Thunderbird < 144, and Thunderbird < 140.4.

It is possible to read the advisory at bugzilla.mozilla.org. The identification of this vulnerability is CVE-2025-11709 since 10/13/2025. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 11/16/2025).

The vulnerability scanner Nessus provides a plugin with the ID 270392 (Mozilla Firefox ESR < 115.29), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 144 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (270392) and CERT Bund (WID-SEC-2025-2275). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

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

Productinfo

Type

• Mail Client Software

Vendor

• Mozilla

Name

• Thunderbird

Version

• 143

License

• open-source

Website

• Vendor: https://www.mozilla.org/

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CPE 2.2info

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Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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