CVE-2022-23090
📋 TL;DR
CVE-2022-23090 is a use-after-free vulnerability in FreeBSD's asynchronous I/O implementation where the aio_aqueue function fails to release a credential reference in error cases. This allows attackers to potentially overflow the reference count and exploit the freed memory, potentially leading to privilege escalation or system crashes. Affects FreeBSD systems using the lio_listio system call.
💻 Affected Systems
- FreeBSD
- NetApp products using FreeBSD kernel
📦 What is this software?
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
Freebsd by Freebsd
⚠️ Risk & Real-World Impact
Worst Case
Local privilege escalation to root, kernel memory corruption leading to system compromise or denial of service.
Likely Case
Local privilege escalation from unprivileged user to root, system instability or crashes.
If Mitigated
Limited impact if proper access controls restrict local user accounts and SELinux/AppArmor policies are enforced.
🎯 Exploit Status
Requires local access and knowledge of kernel exploitation techniques. No public exploits known as of advisory publication.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: FreeBSD 13.0-RELEASE p5, FreeBSD 12.2-RELEASE p12, FreeBSD 12.1-RELEASE p14
Vendor Advisory: https://security.freebsd.org/advisories/FreeBSD-SA-22:10.aio.asc
Restart Required: Yes
Instructions:
1. Update FreeBSD using freebsd-update fetch && freebsd-update install
2. Rebuild kernel if using custom kernel
3. Reboot system to load patched kernel
🔧 Temporary Workarounds
Disable aio module
freebsdUnload the aio kernel module to prevent use of vulnerable system calls
kldunload aio
Restrict local user access
allLimit shell access and local code execution capabilities
🧯 If You Can't Patch
- Implement strict access controls to limit local user privileges
- Monitor for suspicious local privilege escalation attempts
🔍 How to Verify
Check if Vulnerable:
Check FreeBSD version with 'uname -a' and compare against affected versionsCheck Version:
uname -aVerify Fix Applied:
Verify kernel version after reboot with 'uname -a' shows patched version📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- System crash dumps
- Failed privilege escalation attempts
Network Indicators:
- None - local vulnerability only
SIEM Query:
Process monitoring for lio_listio system calls from unprivileged users