CVE-2026-105111 Apache Commons BCEL: Class2HTML emits unescaped class strings, enabling stored XSS
Attackers can inject malicious scripts into HTML reports generated by Apache Commons BCEL when processing untrusted class files.
- 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-2026-105111?
CVE-2026-105111 is a low-severity cross-site scripting vulnerability in Apache Commons BCEL, published on 6 Oct 2026. 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
Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in Apache Commons BCEL.
This only happens when you're using Class2HTML to generate webpages for possibly-attacker-controlled class files, where Class2HTML emitters write attacker class-file strings into HTML unescaped (stored XSS in reports).
This issue affects Apache Commons BCEL: before 6.13.0.
Users are recommended to upgrade to version 6.13.0, which fixes the issue.
Weakness: CWE-79
Which versions are affected by CVE-2026-105111?
How do I fix CVE-2026-105111?
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-2026-105111 being exploited?
There is no known exploitation of CVE-2026-105111 in the wild and no public exploit code.
Sources
Also known as AZL-108014, DEBIAN-CVE-2026-105111, GHSA-vpf7-2j6x-pp68, UBUNTU-CVE-2026-105111.