CVE-2021-28308
📋 TL;DR
This vulnerability in the fltk Rust crate allows attackers to read memory outside the intended buffer boundaries due to insufficient input validation in the pixmap constructor. It affects any Rust application using vulnerable versions of the fltk crate. The out-of-bounds read could lead to information disclosure or be combined with other vulnerabilities for more severe attacks.
💻 Affected Systems
- fltk Rust crate
📦 What is this software?
Fltk by Fltk Project
⚠️ Risk & Real-World Impact
Worst Case
Memory corruption leading to arbitrary code execution, complete system compromise, or sensitive data exfiltration.
Likely Case
Application crash (denial of service) or limited information disclosure from adjacent memory regions.
If Mitigated
Application crash with no data loss if proper memory protections are enabled.
🎯 Exploit Status
Exploitation requires crafting specific pixmap input to trigger the out-of-bounds read. No known public exploits at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 0.15.3 and later
Vendor Advisory: https://rustsec.org/advisories/RUSTSEC-2021-0038.html
Restart Required: Yes
Instructions:
1. Update Cargo.toml to require fltk >= 0.15.3
2. Run 'cargo update' to fetch the patched version
3. Rebuild and redeploy your application
4. Restart any running services using the vulnerable version
🔧 Temporary Workarounds
Disable pixmap functionality
allRemove or disable code that uses pixmap features in your application
Remove pixmap-related code from your Rust application
🧯 If You Can't Patch
- Implement input validation for all pixmap data before passing to fltk functions
- Run application with memory protection features like ASLR and DEP enabled
🔍 How to Verify
Check if Vulnerable:
Check Cargo.lock or run 'cargo tree | grep fltk' to see the installed versionCheck Version:
cargo tree | grep fltk | head -1Verify Fix Applied:
Verify fltk version is 0.15.3 or higher in Cargo.lock after update📡 Detection & Monitoring
Log Indicators:
- Application crashes with segmentation faults
- Unexpected memory access errors in application logs
Network Indicators:
- Unusual pixmap data being sent to application if network-exposed
SIEM Query:
Application:fltk AND (EventID:1000 OR "segmentation fault" OR "access violation")