Mozilla Thunderbird up to 140 Copy as cURL code injection

Summaryinfo

A vulnerability identified as critical has been detected in Mozilla Thunderbird up to 140. Affected by this vulnerability is an unknown functionality of the component Copy as cURL Handler. Performing a manipulation results in code injection. This vulnerability is identified as CVE-2025-8030. The attack can be initiated remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Mozilla Thunderbird up to 140. This affects some unknown functionality of the component Copy as cURL Handler. The manipulation with an unknown input leads to a code injection vulnerability. CWE is classifying the issue as CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Insufficient escaping in the “Copy as cURL” feature could potentially be used to trick a user into executing unexpected code. This vulnerability affects Firefox < 141, Firefox ESR < 128.13, Firefox ESR < 140.1, Thunderbird < 141, Thunderbird < 128.13, and Thunderbird < 140.1.

The advisory is shared at bugzilla.mozilla.org. This vulnerability is uniquely identified as CVE-2025-8030 since 07/22/2025. The exploitability is told to be difficult. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. 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 08/08/2025). MITRE ATT&CK project uses the attack technique T1059 for this issue.

The vulnerability scanner Nessus provides a plugin with the ID 242581 (Mozilla Thunderbird < 128.13), 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 (242581), EUVD (EUVD-2025-22367) and CERT Bund (WID-SEC-2025-1623). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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

• Mail Client Software

Vendor

• Mozilla

Name

• Thunderbird

Version

• 140

License

• open-source

Website

• Vendor: https://www.mozilla.org/

CPE 2.3info

• 🔒

CPE 2.2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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