GHSA-frg3-gpcx-968f is a critical-severity (CVSS 9.8) remote code execution vulnerability in github.com/apple/swift-nio-ssl. A fix is available for github.com/apple/swift-nio-ssl — see the affected versions and patch details below.
SwiftNIO SSL arbitrary code execution vulnerability
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.
How urgent is this, really
GHSA-frg3-gpcx-968f plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/apple/swift-nio-sslReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects SwiftURL packages — download data is not available via public APIs for these ecosystems.
Description
A SwiftNIO application using TLS may be able to execute arbitrary code. The issue was addressed by signaling that an executable stack is not required. This issue is fixed in SwiftNIO SSL 2.4.1.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦SwiftURL | github.com/apple/swift-nio-ssl | ≥ 2.0.0&&< 2.4.1 | 2.4.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/apple/swift-nio-ssl, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/apple/swift-nio-ssl to 2.4.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-frg3-gpcx-968f 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-frg3-gpcx-968f can be triaged on real exposure rather than presence alone.
Tailored to GHSA-frg3-gpcx-968f. 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-frg3-gpcx-968f in your dependencies?
O3 Security finds GHSA-frg3-gpcx-968f across SwiftURL dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.