CVE-2020-36208
📋 TL;DR
This vulnerability in the Rust conquer-once crate allows thread crossing for non-Send but Sync types, which can lead to memory corruption. It affects Rust applications using vulnerable versions of the conquer-once crate. Attackers could potentially exploit this to cause crashes or execute arbitrary code.
💻 Affected Systems
- conquer-once Rust crate
📦 What is this software?
Conquer Once by Conquer Once Project
⚠️ Risk & Real-World Impact
Worst Case
Memory corruption leading to arbitrary code execution, denial of service, or data corruption in affected Rust applications.
Likely Case
Application crashes, instability, or undefined behavior due to memory corruption in multi-threaded Rust programs.
If Mitigated
No impact if using patched version or if application doesn't use vulnerable concurrency patterns.
🎯 Exploit Status
Exploitation requires specific multi-threading conditions and understanding of Rust's concurrency model.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 0.3.2 and later
Vendor Advisory: https://rustsec.org/advisories/RUSTSEC-2020-0101.html
Restart Required: Yes
Instructions:
1. Update Cargo.toml to specify conquer-once >= 0.3.2
2. Run 'cargo update' to fetch the patched version
3. Rebuild and redeploy your Rust application
🔧 Temporary Workarounds
Avoid vulnerable concurrency patterns
allReview and modify code to avoid patterns that could trigger the thread crossing issue
🧯 If You Can't Patch
- Isolate affected applications in restricted environments
- Implement additional monitoring for crashes or abnormal behavior
🔍 How to Verify
Check if Vulnerable:
Check Cargo.lock or Cargo.toml for conquer-once dependency with version < 0.3.2Check Version:
grep -i conquer-once Cargo.toml Cargo.lockVerify Fix Applied:
Verify Cargo.lock shows conquer-once version 0.3.2 or higher📡 Detection & Monitoring
Log Indicators:
- Application crashes, segmentation faults, or panic messages related to concurrency
Network Indicators:
- Unusual application restarts or service interruptions
SIEM Query:
Application logs containing 'panic', 'segfault', or 'thread' errors from Rust applications