OSV-2026-76 Security exception in org.htmlunit.cyberneko.HTMLTagBalancer.endElement
A security exception in the HTMLTagBalancer component of the HTMLUnit library can cause a denial of service when processing malformed HTML.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is OSV-2026-76?
OSV-2026-76 is a denial of service vulnerability in htmlunit, published on 18 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=476170180
Crash type: Security exception
Crash state:
org.htmlunit.cyberneko.HTMLTagBalancer.endElement
org.htmlunit.cyberneko.HTMLElements$HTMLElementsWithCache.getElement
org.htmlunit.cyberneko.HTMLElements$HTMLElementsWithCache.getElement
Which versions are affected by OSV-2026-76?
1 open source package ship an affected version, including htmlunit.
| Package | Affected | Fixed in |
|---|---|---|
htmlunit OSS-Fuzz | All versions | None |
How do I fix OSV-2026-76?
No fix has been published for OSV-2026-76 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is OSV-2026-76 being exploited?
There is no known exploitation of OSV-2026-76 in the wild and no public exploit code.