Mozilla Thunderbird up to 136 memory corruption

Summaryinfo

A vulnerability marked as critical has been reported in Mozilla Thunderbird up to 136. This issue affects some unknown processing. Performing a manipulation results in memory corruption. This vulnerability is identified as CVE-2025-3030. The attack can be initiated remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Mozilla Thunderbird up to 136. This affects an unknown code. 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 Firefox 136, Thunderbird 136, Firefox ESR 128.8, and Thunderbird 128.8. 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 137, Firefox ESR 128.9, Thunderbird 137, and Thunderbird 128.9.

It is possible to read the advisory at bugzilla.mozilla.org. This vulnerability is uniquely identified as CVE-2025-3030 since 03/31/2025. 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. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 04/15/2026).

The vulnerability scanner Nessus provides a plugin with the ID 233651 (Mozilla Firefox ESR < 128.9), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 137 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (233651). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Mail Client Software

Vendor

• Mozilla

Name

• Thunderbird

Version

• 136

License

• open-source

Website

• Vendor: https://www.mozilla.org/

CPE 2.3info

• 🔍

CPE 2.2info

• 🔍

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

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

Discussion