CVE-2026-40180 — quarkus-openapi-generator
Fix: quarkiverse/quarkus-openapi-generator@08b4064CVE-2026-40180 is a Path Traversal vulnerability in io.quarkiverse.openapi.generator:quarkus-openapi-generator. A fix is available for io.quarkiverse.openapi.generator:quarkus-openapi-generator — see the affected versions and patch details below.
Zip Slip Path Traversal in quarkus-openapi-generator ApicurioCodegenWrapper class
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-40180.
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.
Real-World Exposure
io.quarkiverse.openapi.generator:quarkus-openapi-generatorReal-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
Summary
A path traversal vulnerability was discovered in the quarkus-openapi-generator extension
Details
The unzip() method in ApicurioCodegenWrapper.java extracts ZIP entries without validating that the resolved file path stays within the intended output directory. At line 101, the destination is constructed as new File(toOutputDir, entry.getName()) and the content is written immediately. A malicious ZIP archive containing entries with path traversal sequences (e.g., ../../malicious.java) would write files outside the target directory.
The interesting thing is that the client module in the same repository already has the correct fix. OpenApiGeneratorStreamCodeGen.java at line 137 performs proper normalize() and startsWith() validation. The server module was simply missed.
PoC
This vulnerability is exploitable when an attacker controls or can intercept the ZIP archive served by the Apicurio registry. In environments where the registry connection is over an untrusted network or where TLS is not properly configured, exploitation becomes practical. The attack occurs at build/codegen time.
- Create a ZIP file containing an entry named
../../proof.txtwith arbitrary content - Configure quarkus-openapi-generator to use the server (Apicurio) code generation path
- Serve the malicious ZIP from a controlled or MITM'd Apicurio registry endpoint
- Trigger code generation
- Observe that
proof.txtis written two directories above the intended output
Impact
An attacker who can serve a crafted ZIP to the code generation pipeline could write arbitrary files on the build machine. This could overwrite source files, inject malicious code into the build output, or modify configuration files. In CI/CD environments, this could lead to supply chain compromise.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | io.quarkiverse.openapi.generator:quarkus-openapi-generator | all versions | 2.16.0io.quarkiverse.openapi.generator:quarkus-openapi-generator:2.16.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for io.quarkiverse.openapi.generator:quarkus-openapi-generator, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update io.quarkiverse.openapi.generator:quarkus-openapi-generator to 2.16.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-40180 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-40180 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-40180. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-40180 in your dependencies?
O3 Security finds CVE-2026-40180 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.