GHSA-2mrq-w8pv-5pvq
MEDIUMMalicious input can provoke XSS when preserving comments
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
org.owasp.antisamy:antisamyReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
Impact
There is a potential for a mutation XSS (mXSS) vulnerability in AntiSamy caused by flawed parsing of the HTML being sanitized. To be subject to this vulnerability the preserveComments directive must be enabled in your policy file. As a result, certain crafty inputs can result in elements in comment tags being interpreted as executable when using AntiSamy's sanitized output.
Patches
Patched in AntiSamy 1.7.5 and later. This is due to parsing behavior in the neko-htmlunit dependency, just by updating to a newer version the issue was solved. See important remediation details in the reference given below.
Workarounds
If you cannot upgrade to a fixed version of the library, the following mitigation can be applied until you can upgrade: Manually edit your AntiSamy policy file (e.g., antisamy.xml) by deleting the preserveComments directive or setting its value to false, if present.
As the previously mentioned policy settings are preconditions for the mXSS attack to work, changing them as recommended should be sufficient to protect you against this vulnerability when using a vulnerable version of this library. However, the existing bug would still be present in the parser dependency (neko-htmlunit) and therefore in AntiSamy. The safety of this workaround relies on configurations that may change in the future and don't address the root cause of the vulnerability. As such, it is strongly recommended to upgrade to a fixed version of AntiSamy.
For more information
If you have any questions or comments about this advisory:
Email one of the project co-leaders, listed on the OWASP AntiSamy project page, under "Leaders".
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.owasp.antisamy:antisamy | all versions | 1.7.5 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.owasp.antisamy:antisamy. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update org.owasp.antisamy:antisamy to 1.7.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-2mrq-w8pv-5pvq is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-2mrq-w8pv-5pvq is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-2mrq-w8pv-5pvq. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-2mrq-w8pv-5pvq in your dependencies?
O3 detects GHSA-2mrq-w8pv-5pvq across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.