CVE-2025-2830
By crafting a malformed file name for an attachment in a multipart message, an attacker can trick Thunderbird into including a directory listing of /tmp when the message is forwarded or edited as a new message.
Does this matter?
Lower severity and a low EPSS score (0.36%). Track it; it rarely justifies an emergency change on its own.
Description
By crafting a malformed file name for an attachment in a multipart message, an attacker can trick Thunderbird into including a directory listing of /tmp when the message is forwarded or edited as a new message. This vulnerability could allow attackers to disclose sensitive information from the victim's system. This vulnerability is not limited to Linux; similar behavior has been observed on Windows as well. This vulnerability was fixed in Thunderbird 137.0.2 and Thunderbird 128.9.2.
- CVSS 3.1
- 6.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L
- EPSS
- 0.36% probability · 29th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-22
- Affected
- mozilla/thunderbird
- Source
- security@mozilla.org
EPSS 0.4% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1956379Permissions Required
- https://www.mozilla.org/security/advisories/mfsa2025-26/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-27/Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.