OSV-2025-396 Security exception in com.puppycrawl.tools.checkstyle.grammar.java.JavaLanguageParser.expr
Not scored
Published
Check this codebase for OSV-2025-396 and fix it if it is affected.
What it is: OSV-2025-396 is a denial of service vulnerability in checkstyle, published on 22 May 2025.
Exploitation: There is no known exploitation of OSV-2025-396 in the wild and no public exploit code.
Affected packages and fixed versions:
- checkstyle (OSS-Fuzz): affected all versions; no fix listed
Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.
Reference: https://insights.sbomify.com/OSV-2025-396/ (Markdown: https://insights.sbomify.com/OSV-2025-396/index.md)
A security exception in the Java language parser can cause a denial of service when processing specific inputs.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Not stated
- Victim action needed
- Not needed
- Fix
- None listed
What is OSV-2025-396?
OSV-2025-396 is a denial of service vulnerability in checkstyle, published on 22 May 2025.
Official description
OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=419059436
Crash type: Security exception
Crash state:
com.puppycrawl.tools.checkstyle.grammar.java.JavaLanguageParser.expr
java.base/sun.nio.cs.UTF_8$Encoder.encodeArrayLoop
java.base/sun.nio.cs.UTF_8$Encoder.encodeLoop
Which versions are affected by OSV-2025-396?
1 open source package ship an affected version, including checkstyle.
| Package | Affected | Fixed in |
|---|---|---|
checkstyle OSS-Fuzz | All versions | None |
How do I fix OSV-2025-396?
No fix has been published for OSV-2025-396 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-2025-396 being exploited?
There is no known exploitation of OSV-2025-396 in the wild and no public exploit code.