GHSA-4qqq-9vqf-3h3f
MEDIUMScrapy leaks the authorization header on same-domain but cross-origin redirects
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
scrapyReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Impact
Since version 2.11.1, Scrapy drops the Authorization header when a request is redirected to a different domain. However, it keeps the header if the domain remains the same but the scheme (http/https) or the port change, all scenarios where the header should also be dropped.
In the context of a man-in-the-middle attack, this could be used to get access to the value of that Authorization header
Patches
Upgrade to Scrapy 2.11.2.
Workarounds
There is no easy workaround for unpatched versions of Scrapy. You can replace the built-in redirect middlewares with custom ones patched for this issue, but you have to patch them yourself, manually.
References
This security issue was reported and fixed by @szarny at https://huntr.com/bounties/27f6a021-a891-446a-ada5-0226d619dd1a/.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | scrapy | all versions | 2.11.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for scrapy. 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 scrapy to 2.11.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4qqq-9vqf-3h3f 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-4qqq-9vqf-3h3f 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-4qqq-9vqf-3h3f. 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-4qqq-9vqf-3h3f in your dependencies?
O3 detects GHSA-4qqq-9vqf-3h3f across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.