CVE-2021-45703
📋 TL;DR
CVE-2021-45703 is a memory safety vulnerability in the tectonic_xdv Rust crate where XdvParser::<T>::process can read from uninitialized memory locations. This could allow attackers to read sensitive data from memory or potentially cause crashes. Any Rust application using vulnerable versions of tectonic_xdv is affected.
💻 Affected Systems
- tectonic_xdv Rust crate
📦 What is this software?
Tectonic Xdv by Tectonic Xdv Project
⚠️ Risk & Real-World Impact
Worst Case
Information disclosure of sensitive memory contents, potential remote code execution through memory corruption, or denial of service through application crashes.
Likely Case
Information disclosure leading to exposure of sensitive data like credentials, keys, or application state, or application instability/crashes.
If Mitigated
Limited impact with proper memory safety controls, sandboxing, and input validation in place.
🎯 Exploit Status
Exploitation requires triggering the vulnerable code path with specific inputs. No public exploit code is known.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 0.1.12 and later
Vendor Advisory: https://rustsec.org/advisories/RUSTSEC-2021-0112.html
Restart Required: Yes
Instructions:
1. Update Cargo.toml to specify tectonic_xdv >= 0.1.12. 2. Run 'cargo update' to fetch the patched version. 3. Rebuild and redeploy your application.
🔧 Temporary Workarounds
Remove or disable tectonic_xdv usage
allIf the crate is not essential, remove it from your dependencies or disable code paths that use it.
Remove 'tectonic_xdv' from Cargo.toml dependencies
Run 'cargo update'
🧯 If You Can't Patch
- Implement strict input validation and sanitization for all inputs to the tectonic_xdv parser.
- Deploy the application in a sandboxed environment with limited memory access to contain potential information disclosure.
🔍 How to Verify
Check if Vulnerable:
Check Cargo.lock or run 'cargo tree | grep tectonic_xdv' to see if version < 0.1.12 is used.Check Version:
cargo tree | grep tectonic_xdvVerify Fix Applied:
Confirm tectonic_xdv version is >= 0.1.12 in Cargo.lock after update.📡 Detection & Monitoring
Log Indicators:
- Application crashes, segmentation faults, or abnormal termination logs related to tectonic_xdv processing.
Network Indicators:
- Unusual patterns of requests to endpoints that process XDV files or use tectonic_xdv functionality.
SIEM Query:
Search for application logs containing 'tectonic_xdv' alongside crash or error indicators.🔗 References
- https://raw.githubusercontent.com/rustsec/advisory-db/main/crates/tectonic_xdv/RUSTSEC-2021-0112.md
- https://rustsec.org/advisories/RUSTSEC-2021-0112.html
- https://raw.githubusercontent.com/rustsec/advisory-db/main/crates/tectonic_xdv/RUSTSEC-2021-0112.md
- https://rustsec.org/advisories/RUSTSEC-2021-0112.html
