CVE-2024-30171
📋 TL;DR
This vulnerability in Bouncy Castle's Java TLS implementation allows timing-based side-channel attacks during RSA handshakes. Attackers can potentially recover private keys by analyzing timing differences in exception processing. Affects applications using Bouncy Castle's TLS API or JSSE Provider for RSA-based TLS connections.
💻 Affected Systems
- Bouncy Castle Java TLS API
- Bouncy Castle JSSE Provider
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Full compromise of TLS private keys leading to decryption of intercepted traffic, impersonation of servers, or man-in-the-middle attacks.
Likely Case
Partial key recovery requiring significant computational resources and network access, potentially enabling targeted decryption of specific sessions.
If Mitigated
Minimal impact with proper network segmentation, key rotation, and monitoring for unusual TLS handshake patterns.
🎯 Exploit Status
Requires precise timing measurements and multiple handshake attempts. Practical exploitation is challenging but theoretically possible.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.78
Vendor Advisory: https://www.bouncycastle.org/latest_releases.html
Restart Required: Yes
Instructions:
1. Download Bouncy Castle 1.78 from official repository. 2. Replace existing bcprov-jdk*.jar and bctls-jdk*.jar files. 3. Update Maven/Gradle dependencies to version 1.78. 4. Restart affected Java applications.
🔧 Temporary Workarounds
Disable RSA-based TLS
allConfigure TLS to use ECC cipher suites only, avoiding RSA handshakes
java -Dhttps.cipherSuites=TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
🧯 If You Can't Patch
- Implement network segmentation to limit access to vulnerable TLS endpoints
- Enable TLS session resumption to reduce handshake frequency and exposure
🔍 How to Verify
Check if Vulnerable:
Check Bouncy Castle library version in classpath: java -cp bcprov-jdk*.jar org.bouncycastle.jce.provider.BouncyCastleProvider | grep versionCheck Version:
java -cp bcprov-jdk*.jar org.bouncycastle.jce.provider.BouncyCastleProvider | grep 'BouncyCastle Security Provider v'Verify Fix Applied:
Verify installed version is 1.78 or higher using same command📡 Detection & Monitoring
Log Indicators:
- Unusual number of failed TLS handshakes
- Multiple connection attempts from single source with timing patterns
Network Indicators:
- High volume of TLS handshake requests to specific endpoints
- Unusual timing patterns in TLS negotiation packets
SIEM Query:
source="*tls*" AND (event="handshake_failure" OR event="protocol_version") | stats count by src_ip dest_ip🔗 References
- https://github.com/bcgit/bc-csharp/wiki/CVE%E2%80%902024%E2%80%9030171
- https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902024%E2%80%9030171
- https://security.netapp.com/advisory/ntap-20240614-0008/
- https://www.bouncycastle.org/latest_releases.html
- https://github.com/bcgit/bc-csharp/wiki/CVE%E2%80%902024%E2%80%9030171
- https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902024%E2%80%9030171
- https://security.netapp.com/advisory/ntap-20240614-0008/
- https://www.bouncycastle.org/latest_releases.html
