CVE-2023-33202 is a medium-severity (CVSS 5.5) Uncontrolled Resource Consumption vulnerability in org.bouncycastle:bcprov-ext-jdk16. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for org.bouncycastle:bcprov-ext-jdk16 — see the affected versions and patch details below.
Bouncy Castle Denial of Service (DoS)
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-33202.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
org.bouncycastle:bcprov-ext-jdk16☕org.bouncycastle:bcprov-jdk14☕org.bouncycastle:bcprov-jdk15☕org.bouncycastle:bcprov-jdk15to18☕org.bouncycastle:bcprov-jdk16☕org.bouncycastle:bcprov-jdk15on☕org.bouncycastle:bcpkix-jdk18on☕org.bouncycastle:bcprov-ext-jdk15on+1 moreReal-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
Bouncy Castle for Java before 1.73 contains a potential Denial of Service (DoS) issue within the Bouncy Castle org.bouncycastle.openssl.PEMParser class. This class parses OpenSSL PEM encoded streams containing X.509 certificates, PKCS8 encoded keys, and PKCS7 objects. Parsing a file that has crafted ASN.1 data through the PEMParser causes an OutOfMemoryError, which can enable a denial of service attack. (For users of the FIPS Java API: BC-FJA 1.0.2.3 and earlier are affected; BC-FJA 1.0.2.4 is fixed.)
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.bouncycastle:bcprov-ext-jdk16 | all versions | 1.73org.bouncycastle:bcprov-ext-jdk16:1.73 |
| ☕Maven | org.bouncycastle:bcprov-jdk14 | all versions | 1.73org.bouncycastle:bcprov-jdk14:1.73 |
| ☕Maven | org.bouncycastle:bcprov-jdk15 | all versions | 1.73org.bouncycastle:bcprov-jdk15:1.73 |
| ☕Maven | org.bouncycastle:bcprov-jdk15to18 | all versions | 1.73org.bouncycastle:bcprov-jdk15to18:1.73 |
| ☕Maven | org.bouncycastle:bcprov-jdk16 | all versions | 1.73org.bouncycastle:bcprov-jdk16:1.73 |
| ☕Maven | org.bouncycastle:bcprov-jdk15on | all versions | No fix |
Affected Products
bouncy castle for javabouncycastlefips java apibouncycastleResearch 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-ext-jdk16, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.bouncycastle:bcprov-ext-jdk16 to 1.73 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-33202 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.Source: Red Hat security advisory for CVE-2023-33202 (CC BY 4.0)
Frequently Asked Questions
Is CVE-2023-33202 in your dependencies?
Find it across Maven, including transitive dependencies.