CVE-2020-35892
📋 TL;DR
This vulnerability in the simple-slab Rust crate allows attackers to read memory outside the intended bounds of a data structure via the index() function. This affects any Rust application using vulnerable versions of simple-slab for memory management. The out-of-bounds read can expose sensitive information or crash applications.
💻 Affected Systems
- simple-slab Rust crate
📦 What is this software?
Simple Slab by Simple Slab Project
⚠️ Risk & Real-World Impact
Worst Case
Information disclosure of sensitive memory contents including passwords, keys, or other application data, potentially leading to full system compromise if combined with other vulnerabilities.
Likely Case
Application crashes (denial of service) or exposure of non-sensitive memory contents, potentially enabling further exploitation.
If Mitigated
Limited impact if proper memory isolation and sandboxing are in place, though information leakage may still occur.
🎯 Exploit Status
The vulnerability is straightforward to exploit by calling index() with out-of-bounds parameters. Public advisories include exploitation details.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 0.3.3
Vendor Advisory: https://rustsec.org/advisories/RUSTSEC-2020-0039.html
Restart Required: Yes
Instructions:
1. Update Cargo.toml to specify simple-slab version '>=0.3.3'. 2. Run 'cargo update' to fetch the patched version. 3. Rebuild and redeploy your application. 4. Restart any running services using the updated application.
🔧 Temporary Workarounds
Remove simple-slab dependency
allReplace simple-slab with alternative memory management solutions in your Rust codebase.
cargo remove simple-slab
Manually replace simple-slab usage with alternative crates
🧯 If You Can't Patch
- Isolate affected applications in containers or VMs with strict memory limits
- Implement network segmentation to limit access to vulnerable services
🔍 How to Verify
Check if Vulnerable:
Check Cargo.lock or run 'cargo tree | grep simple-slab' to see if version <0.3.3 is present.Check Version:
grep simple-slab Cargo.lock | head -1Verify Fix Applied:
Verify Cargo.lock shows simple-slab version 0.3.3 or higher, and run application tests to ensure functionality.📡 Detection & Monitoring
Log Indicators:
- Application crashes with segmentation faults
- Unexpected memory access errors in Rust panic messages
Network Indicators:
- Unusual patterns of requests to endpoints using simple-slab functionality
SIEM Query:
source="application_logs" AND ("segmentation fault" OR "out of bounds" OR "index out of range")