CVE-2024-27099
📋 TL;DR
CVE-2024-27099 is a double-free vulnerability in the uAMQP C library used for AMQP 1.0 communication with Azure Cloud Services. When processing a malformed AMQP_VALUE in a failed state, it can trigger a double-free condition that may lead to remote code execution. This affects any application or service using the vulnerable uAMQP library to communicate with Azure services.
💻 Affected Systems
- Azure uAMQP C library
- Applications using azure-uamqp-c library
📦 What is this software?
Azure Uamqp by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution with full system compromise, allowing attackers to execute arbitrary code, steal data, or pivot to other systems.
Likely Case
Denial of service through application crashes, with potential for memory corruption leading to information disclosure or limited code execution.
If Mitigated
Application instability or crashes without code execution if memory corruption doesn't lead to exploitable conditions.
🎯 Exploit Status
Exploitation requires sending specially crafted AMQP messages to trigger the double-free condition.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Commit 2ca42b6e4e098af2d17e487814a91d05f6ae4987
Vendor Advisory: https://github.com/Azure/azure-uamqp-c/security/advisories/GHSA-6rh4-fj44-v4jj
Restart Required: Yes
Instructions:
1. Update the azure-uamqp-c submodule to commit 2ca42b6e4e098af2d17e487814a91d05f6ae4987 or later. 2. Rebuild and redeploy any applications using the library. 3. Restart affected services.
🔧 Temporary Workarounds
Network segmentation
allRestrict network access to AMQP endpoints to trusted sources only
Input validation
allImplement additional AMQP message validation before passing to uAMQP library
🧯 If You Can't Patch
- Implement strict network controls to limit AMQP traffic to trusted sources only
- Deploy memory protection mechanisms like ASLR and DEP if not already enabled
🔍 How to Verify
Check if Vulnerable:
Check if your application uses azure-uamqp-c library and verify the version/commit hashCheck Version:
git log --oneline | grep -i "2ca42b6e4e098af2d17e487814a91d05f6ae4987"Verify Fix Applied:
Confirm the library includes commit 2ca42b6e4e098af2d17e487814a91d05f6ae4987 or later📡 Detection & Monitoring
Log Indicators:
- Application crashes with memory corruption errors
- Unexpected process terminations
- High memory usage patterns
Network Indicators:
- Unusual AMQP traffic patterns
- Malformed AMQP messages from unexpected sources
SIEM Query:
process:crash AND (library:"uamqp" OR process:"amqp")🔗 References
- https://github.com/Azure/azure-uamqp-c/commit/2ca42b6e4e098af2d17e487814a91d05f6ae4987
- https://github.com/Azure/azure-uamqp-c/security/advisories/GHSA-6rh4-fj44-v4jj
- https://github.com/Azure/azure-uamqp-c/commit/2ca42b6e4e098af2d17e487814a91d05f6ae4987
- https://github.com/Azure/azure-uamqp-c/security/advisories/GHSA-6rh4-fj44-v4jj
