GHSA-qhp6-635j-x7r2
MEDIUMStatic Web Server affected by timing-based username enumeration in Basic Authentication due to early response on invalid usernames
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.
Blast Radius
static-web-serverReal-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
Summary
A Timing-based username enumeration in Basic Authentication vulnerability due to early response on invalid usernames could allow attackers to identify valid users and focus their efforts on targeted brute-force or credential-stuffing attacks.
Details
SWS validates the provided username before performing any password verification.
- Invalid Username: The server returns a
401 Unauthorizedresponse immediately. - Valid Username: The server proceeds to verify the password (e.g., using
bcrypt), which introduces a different execution path and measurable timing discrepancy.
This allows an attacker to distinguish between existing and non-existing accounts by analyzing response times.
PoC
The following statistical results were obtained by measuring the mean response time over 100 iterations using a custom Rust script:
| User Type | Average Response Time |
|---|---|
| Invalid User | 0.409861 ms |
| Valid User | 0.250925 ms |
| Difference | ~0.158936 ms |
While the valid user responded faster in this specific test environment, the statistically significant gap confirms that the authentication logic does not execute in constant time.
Impact
Users using the SWS' Basic Authentication feature are primarily impacted.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | static-web-server | ≥ 2.1.0&&< 2.41.0 | 2.41.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for static-web-server. 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 static-web-server to 2.41.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-qhp6-635j-x7r2 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 GHSA-qhp6-635j-x7r2 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 GHSA-qhp6-635j-x7r2. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-qhp6-635j-x7r2 in your dependencies?
O3 detects GHSA-qhp6-635j-x7r2 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.