CVE-2026-25210 Integer overflow in libexpat
An integer overflow in libexpat's buffer size calculation can lead to memory corruption, potentially allowing denial of service or code execution.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-25210?
CVE-2026-25210 is a medium-severity vulnerability in Libexpat Project Libexpat, published on 30 Jan 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In libexpat before 2.7.4, the doContent function does not properly determine the buffer size bufSize because there is no integer overflow check for tag buffer reallocation.
Weakness: CWE-190
Which versions are affected by CVE-2026-25210?
It affects 1 product.
Products include Libexpat Project Libexpat.
How do I fix CVE-2026-25210?
Upgrade to a fixed version.
Is CVE-2026-25210 being exploited?
There is no known exploitation of CVE-2026-25210 in the wild and no public exploit code.
Other vulnerabilities in Libexpat Project Libexpat
Sources
Also known as ALPINE-CVE-2026-25210, AZL-75815, AZL-76340, BELL-CVE-2026-25210, CLEANSTART-2026-QP18579, CLSA-2026-1773924425 and 22 more.