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
@misskey-dev/summalyReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects npm packages — download data is not available via public APIs for these ecosystems.
Description
Summary
A logic error in the main summaly function causes the allowRedirects option to never be passed to any plugins, and as a result, isn't enforced.
Details
In the main summaly function, a new scrapingOptions object is created and passed to either the matched plugin, if any, or the default summarize function. The issue here is that the new scrapingOptions object is not provided the allowRedirects property of opts.
PoC
- Publish a post containing a link to any URL that redirects on Misskey.
- A preview will be generated for the target of the redirect, despite Misskey passing
allowRedirects: false.
Impact
Misskey will follow redirects, despite explicitly requesting not to.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @misskey-dev/summaly | ≥ 3.0.1&&< 5.2.1 | 5.2.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @misskey-dev/summaly. 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 @misskey-dev/summaly to 5.2.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-7899-w6c4-vqc4 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-7899-w6c4-vqc4 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-7899-w6c4-vqc4. 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-7899-w6c4-vqc4 in your dependencies?
O3 detects GHSA-7899-w6c4-vqc4 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.