Mozilla Thunderbird Black Fade Animation clickjacking

Summaryinfo

A vulnerability has been found in Mozilla Thunderbird and classified as problematic. Impacted is an unknown function of the component Black Fade Animation Handler. This manipulation causes clickjacking. The identification of this vulnerability is CVE-2023-6206. It is possible to initiate the attack remotely. There is no exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as problematic was found in Mozilla Thunderbird (Mail Client Software) (the affected version unknown). Affected by this vulnerability is an unknown part of the component Black Fade Animation Handler. The manipulation with an unknown input leads to a clickjacking vulnerability. The CWE definition for the vulnerability is CWE-451. The user interface (UI) does not properly represent critical information to the user, allowing the information - or its source - to be obscured or spoofed. This is often a component in phishing attacks. As an impact it is known to affect integrity. The summary by CVE is:

The black fade animation when exiting fullscreen is roughly the length of the anti-clickjacking delay on permission prompts. It was possible to use this fact to surprise users by luring them to click where the permission grant button would be about to appear. This vulnerability affects Firefox < 120, Firefox < 115.5, and Thunderbird < 115.5.0.

The weakness was shared 11/21/2023. It is possible to read the advisory at bugzilla.mozilla.org. This vulnerability is known as CVE-2023-6206 since 11/20/2023. 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 06/19/2025). The attack technique deployed by this issue is T1566.003 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 239860 (TencentOS Server 2: firefox (TSSA-2023:0316)), 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 (239860). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Mail Client Software

Vendor

• Mozilla

Name

• Thunderbird

License

• open-source

Website

• Vendor: https://www.mozilla.org/

CPE 2.3info

• 🔍

CPE 2.2info

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Entryinfo

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

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