CVE-2024-4741
📋 TL;DR
This CVE describes a use-after-free vulnerability in OpenSSL's SSL_free_buffers function. Only applications that directly call this rarely-used function are affected, potentially allowing memory corruption, crashes, or arbitrary code execution. Most applications are not vulnerable since they don't call SSL_free_buffers.
💻 Affected Systems
- OpenSSL
⚠️ 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
Arbitrary code execution leading to complete system compromise if an attacker can trigger the use-after-free condition and chain with other vulnerabilities.
Likely Case
Application crashes or instability due to memory corruption when SSL_free_buffers is called inappropriately.
If Mitigated
No impact for applications that don't call SSL_free_buffers function.
🎯 Exploit Status
Requires applications to call SSL_free_buffers function, which is rarely used. No known active exploitation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions containing commits: 704f725b96aa373ee45ecfb23f6abfe8be8d9177, b3f0eb0a295f58f16ba43ba99dad70d4ee5c437d, c88c3de51020c37e8706bf7a682a162593053aac, e5093133c35ca82874ad83697af76f4b0f7e3bd8, f7a045f3143fc6da2ee66bf52d8df04829590dd4
Vendor Advisory: https://github.openssl.org/openssl/extended-releases/commit/f7a045f3143fc6da2ee66bf52d8df04829590dd4
Restart Required: Yes
Instructions:
1. Identify OpenSSL version in use. 2. Update to patched version containing the fix commits. 3. Recompile applications if statically linked. 4. Restart affected services.
🔧 Temporary Workarounds
Avoid SSL_free_buffers calls
allModify application code to avoid calling SSL_free_buffers function entirely.
# Review application source code for SSL_free_buffers() calls
# Remove or comment out SSL_free_buffers() calls
🧯 If You Can't Patch
- Audit all applications for SSL_free_buffers function calls and remove them
- Implement strict input validation and network monitoring for TLS/SSL connections
🔍 How to Verify
Check if Vulnerable:
Check if application code calls SSL_free_buffers() function. Check OpenSSL version against patched versions.Check Version:
openssl versionVerify Fix Applied:
Verify OpenSSL version contains the fix commits. Test application functionality after patch.📡 Detection & Monitoring
Log Indicators:
- Application crashes with memory access violations
- Segmentation faults in OpenSSL-related processes
Network Indicators:
- Unusual TLS/SSL connection patterns triggering buffer operations
SIEM Query:
Process crashes with OpenSSL library in stack trace OR Application logs containing SSL_free_buffers errors🔗 References
- https://github.com/openssl/openssl/commit/704f725b96aa373ee45ecfb23f6abfe8be8d9177
- https://github.com/openssl/openssl/commit/b3f0eb0a295f58f16ba43ba99dad70d4ee5c437d
- https://github.com/openssl/openssl/commit/c88c3de51020c37e8706bf7a682a162593053aac
- https://github.com/openssl/openssl/commit/e5093133c35ca82874ad83697af76f4b0f7e3bd8
- https://github.openssl.org/openssl/extended-releases/commit/f7a045f3143fc6da2ee66bf52d8df04829590dd4
- https://www.openssl.org/news/secadv/20240528.txt
- https://lists.debian.org/debian-lts-announce/2024/10/msg00033.html
- https://lists.debian.org/debian-lts-announce/2024/11/msg00000.html
- https://security.netapp.com/advisory/ntap-20240621-0004/
