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
org.slf4j:slf4j-ext☕org.slf4j:slf4j-extReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
org.slf4j.ext.EventData in the slf4j-ext module in QOS.CH SLF4J before 1.8.0-beta4 allows remote attackers to bypass intended access restrictions via crafted data. EventData in the slf4j-ext module in QOS.CH SLF4J, has been fixed in SLF4J version 1.7.26 and later and in the 2.0.x series.
Note that while the fix commit is associated with the tag 1.8.0-beta3, the versions in Maven go directly from 1.8.0-beta2 to 1.8.0-beta4.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.slf4j:slf4j-ext | all versions | 1.7.26 |
| ☕Maven | org.slf4j:slf4j-ext | ≥ 1.8.0-alpha0&&< 1.8.0-beta4 | 1.8.0-beta4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.slf4j:slf4j-ext. 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 org.slf4j:slf4j-ext to 1.7.26 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-w77p-8cfg-2x43 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-w77p-8cfg-2x43 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-w77p-8cfg-2x43. 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-w77p-8cfg-2x43 in your dependencies?
O3 detects GHSA-w77p-8cfg-2x43 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.