Mozilla Firefox/Thunderbird/Firefox ESR Video Element use after free

Summaryinfo

A vulnerability identified as problematic has been detected in Mozilla Firefox, Thunderbird and Firefox ESR. This affects an unknown function of the component Video Element Handler. The manipulation leads to use after free. This vulnerability is listed as CVE-2019-11746. The attack may be initiated remotely. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Mozilla Firefox, Thunderbird and Firefox ESR (Web Browser) (affected version not known) and classified as problematic. This issue affects some unknown functionality of the component Video Element Handler. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is availability. The summary by CVE is:

A use-after-free vulnerability can occur while manipulating video elements if the body is freed while still in use. This results in a potentially exploitable crash. This vulnerability affects Firefox < 69, Thunderbird < 68.1, Thunderbird < 60.9, Firefox ESR < 60.9, and Firefox ESR < 68.1.

The weakness was presented 09/27/2019 as MFSA 2019-25 as confirmed security advisory (Website). It is possible to read the advisory at mozilla.org. The identification of this vulnerability is CVE-2019-11746 since 05/03/2019. 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 $0-$5k at the moment (estimation calculated on 11/26/2025).

Upgrading eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

See VDB-142392, VDB-142393, VDB-142394 and VDB-142395 for similar entries. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Web Browser

Vendor

• Mozilla

Name

• Firefox
• Firefox ESR
• Thunderbird

License

• open-source

Website

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

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Entryinfo

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