CVE-2025-1015 Unsanitized address book fields
Attackers can inject malicious JavaScript into Thunderbird address book fields, executing code when victims import and click the links.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2025-1015?
CVE-2025-1015 is a medium-severity cross-site scripting vulnerability in Mozilla Thunderbird, published on 4 Feb 2025. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
The Thunderbird Address Book URI fields contained unsanitized links. This could be used by an attacker to create and export an address book containing a malicious payload in a field. For example, in the “Other” field of the Instant Messaging section. If another user imported the address book, clicking on the link could result in opening a web page inside Thunderbird, and that page could execute (unprivileged) JavaScript. This vulnerability was fixed in Thunderbird 128.7 and Thunderbird 135.
Weakness: CWE-79
Which versions are affected by CVE-2025-1015?
It affects 1 product.
Products include Mozilla Thunderbird.
How do I fix CVE-2025-1015?
Upgrade to a fixed version.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2025-1015 being exploited?
There is no known exploitation of CVE-2025-1015 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Other vulnerabilities in Mozilla Thunderbird
Sources
Also known as DEBIAN-CVE-2025-1015, GHSA-w5j5-j57f-hp27, UBUNTU-CVE-2025-1015.