CVE-2020-28052
HIGHCVE-2020-28052 is a high-severity (CVSS 8.1) vulnerability in org.bouncycastle:bcprov-jdk15to18. 1 public exploit reference exists, so weaponization risk is real. O3 Security confirms whether CVE-2020-28052 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Logic error in Legion of the Bouncy Castle BC Java
Real-World Exposure
org.bouncycastle:bcprov-jdk15to18☕org.bouncycastle:bcprov-jdk15☕org.bouncycastle:bcprov-jdk15on☕org.bouncycastle:bcprov-ext-jdk15on☕org.bouncycastle:bcprov-jdk14☕org.bouncycastle:bcprov-jdk16☕org.bouncycastle:bcprov-ext-jdk16Real-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
An issue was discovered in Legion of the Bouncy Castle BC Java 1.65 and 1.66. The OpenBSDBCrypt.checkPassword utility method compared incorrect data when checking the password, allowing incorrect passwords to indicate they were matching with previously hashed ones that were different.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.bouncycastle:bcprov-jdk15to18 | ≥ 1.65&&< 1.67 | 1.67 |
| ☕Maven | org.bouncycastle:bcprov-jdk15 | ≥ 1.65&&< 1.67 | 1.67 |
| ☕Maven | org.bouncycastle:bcprov-jdk15on | ≥ 1.65&&< 1.67 | 1.67 |
| ☕Maven | org.bouncycastle:bcprov-ext-jdk15on | ≥ 1.65&&< 1.67 | 1.67 |
| ☕Maven | org.bouncycastle:bcprov-jdk14 | ≥ 1.65&&< 1.67 | 1.67 |
| ☕Maven | org.bouncycastle:bcprov-jdk16 | ≥ 1.65&&< 1.67 | 1.67 |
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 org.bouncycastle:bcprov-jdk15to18. 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.bouncycastle:bcprov-jdk15to18 to 1.67 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-28052 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-2020-28052 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-2020-28052. 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-2020-28052 in your dependencies?
O3 detects CVE-2020-28052 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.