CVE-2020-8908
LOWInformation Disclosure in Guava
Blast Radius
com.google.guava:guavaReal-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
A temp directory creation vulnerability exists in all versions of Guava, allowing an attacker with access to the machine to potentially access data in a temporary directory created by the Guava API com.google.common.io.Files.createTempDir(). By default, on unix-like systems, the created directory is world-readable (readable by an attacker with access to the system). The method in question has been marked @Deprecated in versions 30.0 and later and should not be used. For Android developers, we recommend choosing a temporary directory API provided by Android, such as context.getCacheDir(). For other Java developers, we recommend migrating to the Java 7 API java.nio.file.Files.createTempDirectory() which explicitly configures permissions of 700, or configuring the Java runtime's java.io.tmpdir system property to point to a location whose permissions are appropriately configured.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | com.google.guava:guava | all versions | 32.0.0-android |
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 com.google.guava:guava. 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 com.google.guava:guava to 32.0.0-android or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-8908 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 CVE-2020-8908 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 CVE-2020-8908. 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-2020-8908 in your dependencies?
O3 detects CVE-2020-8908 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.