Mozilla Thunderbird up to 150.0.0 memory corruption

Summaryinfo

A vulnerability has been found in Mozilla Thunderbird up to 150.0.0 and classified as critical. Affected is an unknown function. Performing a manipulation results in memory corruption. This vulnerability is known as CVE-2026-7323. Remote exploitation of the attack is possible. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as critical, was found in Mozilla Thunderbird up to 150.0.0. This affects an unknown part. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Memory safety bugs present in Thunderbird ESR 140.10.0 and Thunderbird 150.0.0. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 150.0.1, Firefox ESR 140.10.1, Thunderbird 150.0.1, and Thunderbird 140.10.1.

The advisory is shared at bugzilla.mozilla.org. This vulnerability is uniquely identified as CVE-2026-7323 since 04/28/2026. The exploitability is told to be easy. 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 07/02/2026).

The vulnerability scanner Nessus provides a plugin with the ID 311845 (Debian dla-4562 : thunderbird - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 150.0.1 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (311845) and CERT Bund (WID-SEC-2026-1296). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Debian Linux
• Red Hat Enterprise Linux
• SUSE Linux
• IGEL OS
• SUSE openSUSE
• Mozilla Firefox
• Mozilla Firefox ESR
• Mozilla Thunderbird
• Amazon Linux 2
• RESF Rocky Linux
• Oracle Linux

Productinfo

Type

• Mail Client Software

Vendor

• Mozilla

Name

• Thunderbird

Version

• 150.0

License

• open-source

Website

• Vendor: https://www.mozilla.org/

CPE 2.3info

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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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