CVE-2025-0238 Use-after-free when breaking lines in text
An attacker can trigger a use-after-free via controlled memory allocation failures, potentially leading to code execution or crashes in Firefox and Thunderbird.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-0238?
CVE-2025-0238 is a medium-severity use after free vulnerability in Mozilla Firefox, published on 7 Jan 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Assuming a controlled failed memory allocation, an attacker could have caused a use-after-free, leading to a potentially exploitable crash. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Firefox ESR 115.19, Thunderbird 134, and Thunderbird 128.6.
Weakness: CWE-416
Which versions are affected by CVE-2025-0238?
It affects 2 products.
Products include Mozilla Firefox, Mozilla Thunderbird.
How do I fix CVE-2025-0238?
Upgrade to a fixed version.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2025-0238 being exploited?
There is no known exploitation of CVE-2025-0238 in the wild and no public exploit code.
Other vulnerabilities in Mozilla Firefox
Sources
Also known as DEBIAN-CVE-2025-0238, GHSA-phcc-6pmp-qw9v, UBUNTU-CVE-2025-0238.