Mozilla Firefox/Firefox ESR/Thunderbird WebRTC out-of-bounds write

Summaryinfo

A vulnerability identified as critical has been detected in Mozilla Firefox, Firefox ESR and Thunderbird. Affected by this vulnerability is an unknown functionality of the component WebRTC. This manipulation causes out-of-bounds write. This vulnerability appears as CVE-2019-11760. The attack may be initiated remotely. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability has been found in Mozilla Firefox, Firefox ESR and Thunderbird (Web Browser) (affected version not known) and classified as critical. Affected by this vulnerability is some unknown functionality of the component WebRTC. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. The CWE definition for the vulnerability is CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

A fixed-size stack buffer could overflow in nrappkit when doing WebRTC signaling. This resulted in a potentially exploitable crash in some instances. This vulnerability affects Firefox < 70, Thunderbird < 68.2, and Firefox ESR < 68.2.

The weakness was presented 01/08/2020 as Bug 1577719 as not defined bug report (Bugzilla). It is possible to read the advisory at bugzilla.mozilla.org. This vulnerability is known as CVE-2019-11760 since 05/03/2019. 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. 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 08/17/2025).

The vulnerability scanner Nessus provides a plugin with the ID 250082 (Linux Distros Unpatched Vulnerability : CVE-2019-11760), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (250082). See VDB-148427, VDB-148426, VDB-148425 and VDB-148424 for similar entries. Be aware that VulDB is the high quality source 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

Be aware that VulDB is the high quality source for vulnerability data.

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