GHSA-pc22-3g76-gm6j is a critical-severity (CVSS 9.3) CWE-378 vulnerability in io.swagger:swagger-codegen. 1 public exploit reference exists, so weaponization risk is real. O3 Security confirms whether GHSA-pc22-3g76-gm6j is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Generator Web Application: Local Privilege Escalation Vulnerability via System Temp Directory
Real-World Exposure
io.swagger:swagger-codegenReal-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
On Unix like systems, the system's temporary directory is shared between all users on that system. A collocated user can observe the process of creating a temporary sub directory in the shared temporary directory and race to complete the creation of the temporary subdirectory.
This vulnerability is local privilege escalation because the contents of the outputFolder can be appended to by an attacker. As such, code written to this directory, when executed can be attacker controlled.
Java Code
The method File.createTempFile from the JDK is vulnerable to this local information disclosure vulnerability.
Patches
Fix has been applied to the master branch with:
included in release: 2.4.19
References
- CWE-378: Creation of Temporary File With Insecure Permissions
- CWE-379: Creation of Temporary File in Directory with Insecure Permissions
For more information
If you have any questions or comments about this advisory:
- Email us at [email protected]
Original vulnerability report
I'm performing OSS security research under the GitHub Security Lab Bug Bounty program. I've been using a custom CodeQL query to find local temporary directory vulnerabilities in OSS with three custom CodeQL queries.
- https://github.com/github/codeql/pull/4388/files#diff-71d36c0f2bd0b08e32866f873f1c906cdc17277e0ad327c0c6cd2c882f30de4f
- https://github.com/github/codeql/pull/4388/files#diff-1893a18a8bf43c011d61a7889d0139b998a5a78701a30fe7722eddd4c506aaac
- https://github.com/github/codeql/pull/4473
The code generated by the Swagger Generator contains a local information disclosure vulnerability. The system temporary directory, on unix-like systems is shared between multiple users. Information written to this directory, or directories created under this directory that do not correctly set the posix standard permissions can have these directories read/modified by other users.
This vulnerability exists in the maven plugin.
This vulnerability is distinctly different. This vulnerability is most likely a local privilege escalation vulnerability.
This vulnerability is very similar to this similar vulnerability I disclosed in the Eclipse Jetty project.
https://github.com/eclipse/jetty.project/security/advisories/GHSA-g3wg-6mcf-8jj6
This is due to a race condition between the call to
deleteand the call tomkdirs.// ensure file will always be unique by appending random digits File outputFolder = File.createTempFile("codegen-", "-tmp"); // Attacker knows the full path of the file that will be generated // delete the file that was created outputFolder.delete(); // Attacker sees file is deleted and begins a race to create their own directory before Swagger Code Generator. // and make a directory of the same name // SECURITY VULNERABILITY: Race Condition! - Attacker beats Swagger Code Generator and now owns this directory outputFolder.mkdirs();This vulnerability is local privilege escalation because the contents of the
outputFoldercan be appended to by an attacker. As such, code written to this directory, when executed can be attacker controlled.The fix here is to switch to the
FilesAPI for creating temporary directories. Which does not contain this race condition, and appropriately sets the correct file permissions.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | io.swagger:swagger-codegen | all versions | 2.4.19 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for io.swagger:swagger-codegen. 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 io.swagger:swagger-codegen to 2.4.19 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-pc22-3g76-gm6j 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-pc22-3g76-gm6j 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-pc22-3g76-gm6j. 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-pc22-3g76-gm6j in your dependencies?
O3 detects GHSA-pc22-3g76-gm6j across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.