Mozilla Thunderbird on Windows Handle use after free

Summaryinfo

A vulnerability classified as critical has been found in Mozilla Thunderbird on Windows. Impacted is an unknown function of the component Handle Handler. This manipulation causes use after free. This vulnerability is handled as CVE-2023-5174. The attack can be initiated remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Mozilla Thunderbird on Windows (Mail Client Software) (version now known) and classified as critical. Affected by this vulnerability is some unknown processing of the component Handle Handler. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

If Windows failed to duplicate a handle during process creation, the sandbox code may have inadvertently freed a pointer twice, resulting in a use-after-free and a potentially exploitable crash. *This bug only affects Firefox on Windows when run in non-standard configurations (such as using `runas`). Other operating systems are unaffected.* This vulnerability affects Firefox < 118, Firefox ESR < 115.3, and Thunderbird < 115.3.

The weakness was released 09/27/2023. The advisory is shared at mozilla.org. This vulnerability is known as CVE-2023-5174 since 09/25/2023. 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 08/16/2025).

The vulnerability scanner Nessus provides a plugin with the ID 250244 (Linux Distros Unpatched Vulnerability : CVE-2023-5174), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability. The upgrade is hosted for download at mozilla.org.

The vulnerability is also documented in the vulnerability database at Tenable (250244). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• Mail Client Software

Vendor

• Mozilla

Name

• Thunderbird

License

• open-source

Website

• Vendor: https://www.mozilla.org/

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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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