Vulnerability Description
Thunderbird parses addresses in a way that can allow sender spoofing in case the server allows an invalid From address to be used. For example, if the From header contains an (invalid) value "Spoofed Name ", Thunderbird treats [email protected] as the actual address. This vulnerability was fixed in Thunderbird 128.10.1 and Thunderbird 138.0.1.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Thunderbird | < 128.10.0 |
Related Weaknesses (CWE)
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1950629Permissions Required
- https://www.mozilla.org/security/advisories/mfsa2025-34/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-35/Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2025/05/msg00022.html
FAQ
What is CVE-2025-3875?
CVE-2025-3875 is a vulnerability with a CVSS score of 7.5 (HIGH). Thunderbird parses addresses in a way that can allow sender spoofing in case the server allows an invalid From address to be used. For example, if the From header contains an (invalid) value "Spoofed ...
How severe is CVE-2025-3875?
CVE-2025-3875 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2025-3875?
Check the references section above for vendor advisories and patch information. Affected products include: Mozilla Thunderbird.