CVE-2018-20989 is a high-severity (CVSS 7.5) CWE-191 vulnerability in untrusted. O3 Security confirms whether CVE-2018-20989 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Integer underflow in untrusted
Real-World Exposure
untrustedReal-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
A mistake in error handling in untrusted before 0.6.2 could lead to an integer underflow and panic if a user of the crate didn't properly check for errors returned by untrusted. Combination of these two programming errors (one in untrusted and another by user of this crate) could lead to a panic and maybe a denial of service of affected software. The error in untrusted is fixed in release 0.6.2 released 2018-06-21. It's also advisable that users of untrusted check for their sources for cases where errors returned by untrusted are not handled correctly.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | untrusted | all versions | 0.6.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for untrusted. 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 untrusted to 0.6.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2018-20989 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-2018-20989 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-2018-20989. 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-2018-20989 in your dependencies?
O3 detects CVE-2018-20989 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.