CVE-2026-2258
📋 TL;DR
CVE-2026-2258 is a memory corruption vulnerability in aardappel lobster's WaveFunctionCollapse function that allows local attackers to execute arbitrary code or cause denial of service. The vulnerability affects aardappel lobster versions up to 2025.4. Attackers must have local access to the system to exploit this flaw.
💻 Affected Systems
- aardappel lobster
📦 What is this software?
Lobster by Strlen
⚠️ Risk & Real-World Impact
Worst Case
Local privilege escalation leading to full system compromise, data theft, or persistent backdoor installation.
Likely Case
Application crash or denial of service affecting the lobster process.
If Mitigated
Limited impact with proper privilege separation and minimal user access.
🎯 Exploit Status
Exploit code is publicly available in GitHub repositories, making exploitation straightforward for attackers with local access.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patched in commit c2047a33e1ac2c42ab7e8704b33f7ea518a11ffd
Vendor Advisory: https://github.com/aardappel/lobster/issues/395
Restart Required: Yes
Instructions:
1. Update aardappel lobster to version after 2025.4 or apply commit c2047a33e1ac2c42ab7e8704b33f7ea518a11ffd. 2. Rebuild from source if using source installation. 3. Restart any services using lobster.
🔧 Temporary Workarounds
Restrict local user access
linuxLimit which users can execute lobster applications to reduce attack surface
chmod 750 /path/to/lobster
setfacl -m u:trusteduser:rx /path/to/lobster
🧯 If You Can't Patch
- Implement strict access controls to limit which users can run lobster applications
- Monitor for abnormal process behavior or crashes related to lobster processes
🔍 How to Verify
Check if Vulnerable:
Check lobster version: lobster --version or examine source code for pre-patch wfc.hCheck Version:
lobster --versionVerify Fix Applied:
Verify commit c2047a33e1ac2c42ab7e8704b33f7ea518a11ffd is present in git log📡 Detection & Monitoring
Log Indicators:
- Segmentation faults in lobster processes
- Abnormal memory usage patterns
- Unexpected process termination
Network Indicators:
- None - local exploitation only
SIEM Query:
process_name:"lobster" AND (event_type:"segmentation_fault" OR exit_code:139)🔗 References
- https://github.com/aardappel/lobster/
- https://github.com/aardappel/lobster/commit/c2047a33e1ac2c42ab7e8704b33f7ea518a11ffd
- https://github.com/aardappel/lobster/issues/395
- https://github.com/aardappel/lobster/issues/395#issuecomment-3849012938
- https://github.com/oneafter/0204/blob/main/lob1/repro.lobster
- https://vuldb.com/?ctiid.345005
- https://vuldb.com/?id.345005
- https://vuldb.com/?submit.753167
