CVE-2023-49582
📋 TL;DR
This CVE allows local users on Unix systems to read Apache Portable Runtime (APR) named shared memory segments due to overly permissive permissions. This could expose sensitive application data stored in shared memory. Only Unix platforms using APR's default shared memory implementation are affected.
💻 Affected Systems
- Apache Portable Runtime (APR)
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Local attackers could read sensitive application data from shared memory, potentially exposing credentials, session tokens, or other confidential information.
Likely Case
Local users with access to the system could read application data from shared memory segments, potentially gaining unauthorized access to information.
If Mitigated
With proper access controls and patching, the risk is limited to authorized local users who shouldn't have access to shared memory segments.
🎯 Exploit Status
Requires local access to the system. Exploitation involves reading shared memory segments that should be protected.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.7.5
Vendor Advisory: https://lists.apache.org/thread/sntjc04t1rvjhdzz2tzmtz2zdnmv7dc4
Restart Required: Yes
Instructions:
1. Download APR 1.7.5 or later from Apache website. 2. Compile and install the updated version. 3. Restart all applications using APR library. 4. Rebuild any applications statically linked to APR.
🔧 Temporary Workarounds
Rebuild with SHMGET flag
linuxRecompile APR with APR_USE_SHMEM_SHMGET=1 to use shmget() instead of vulnerable implementation
./configure --with-apr=/path/to/apr --enable-shmget
make
make install
Restrict shared memory permissions
linuxManually adjust permissions on existing shared memory segments
chmod 600 /dev/shm/apr*
chown root:root /dev/shm/apr*
🧯 If You Can't Patch
- Implement strict access controls to limit local user access to systems running vulnerable APR
- Monitor shared memory access and file permissions for suspicious activity
🔍 How to Verify
Check if Vulnerable:
Check APR version with 'apr-config --version' or examine shared memory permissions with 'ls -la /dev/shm/ | grep apr'Check Version:
apr-config --versionVerify Fix Applied:
Verify APR version is 1.7.5 or later and check that shared memory segments have proper permissions (not world-readable)📡 Detection & Monitoring
Log Indicators:
- Unexpected access to /dev/shm files
- Permission changes on shared memory segments
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
source=*syslog* AND ("/dev/shm/apr" OR "shared memory permission")