CVE-2021-45712
CVE-2021-45712 is a Path Traversal vulnerability in rust-embed. 2 public exploit references exist, so weaponization risk is real. O3 Security confirms whether CVE-2021-45712 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
RustEmbed generated `get` method allows for directory traversal when reading files from disk
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
rust-embedReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
When running in debug mode and the debug-embed (off by default) feature is
not enabled, the generated get method does not check that the input path is
a child of the folder given.
This allows attackers to read arbitrary files in the file system if they have
control over the filename given. The following code will print the contents of
your /etc/passwd if adjusted with a correct number of ../s depending on
where it is run from.
#[derive(rust_embed::RustEmbed)]
#[folder = "src/"]
pub struct Asset;
fn main() {
let d = Asset::get("../../../etc/passwd").unwrap().data;
println!("{}", String::from_utf8_lossy(&d));
}
The flaw was corrected by canonicalizing the input filename and ensuring that it starts with the canonicalized folder path.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | rust-embed | all versions | 6.3.0 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for rust-embed. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update rust-embed to 6.3.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-45712 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2021-45712 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2021-45712. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2021-45712 in your dependencies?
O3 detects CVE-2021-45712 across crates.io dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.