How the CVE Works:
The vulnerability occurs in the `Md::fetch` and `Cipher::fetch` functions of rust-openssl when a `Some(…)` value is passed to the `properties` argument. Due to improper memory handling, a use-after-free (UAF) condition arises. When `CString::drop` executes, it frees the memory prematurely, but OpenSSL may still attempt to access it, treating the properties as an empty string. This could lead to undefined behavior, crashes, or potential exploitation if an attacker controls the freed memory region.
DailyCVE Form:
Platform: rust-openssl
Version:
Vulnerability: Use-After-Free
Severity: Moderate
Date: Apr 4, 2025
What Undercode Say:
Exploitation:
- Trigger UAF: Craft a malicious payload passing `Some(…)` to
properties. - Heap Spraying: Fill freed memory with attacker-controlled data.
- Code Execution: Manipulate OpenSSL into executing unintended operations.
Protection:
1. Update rust-openssl to the latest patched version.
2. Input Validation: Reject invalid `properties` arguments early.
3. Memory Sanitizers: Use `AddressSanitizer` to detect UAF.
Analytics:
- Affected Users: Moderate (developers using rust-openssl).
- Exploit Complexity: Medium (requires heap manipulation).
- Patch Availability: Yes (GitHub Advisory).
Commands & Code:
// Vulnerable Code Example (rust-openssl):
let md = Md::fetch(None, Some("invalid_properties")).unwrap(); // UAF trigger
// Mitigation:
if properties.is_some() {
validate_properties(properties.unwrap()); // Safe check
}
Exploit PoC (Conceptual):
use openssl::hash::Md;
fn trigger_uaf() {
let _ = Md::fetch(None, Some("controlled_data")).unwrap(); // UAF
}
Protection Code:
Cargo.toml
[bash]
openssl = { version = ">=0.10.55", features = ["secure"] } // Patched
Debugging:
RUSTFLAGS="-Zsanitizer=address" cargo run --target x86_64-unknown-linux-gnu
References:
References:
Reported By: https://github.com/advisories/GHSA-4fcv-w3qc-ppgg
Extra Source Hub:
Undercode
