How severe is GHSA-cf3q-gqg7-3fm9?

GHSA-cf3q-gqg7-3fm9 has a CVSS score of 6.5/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-cf3q-gqg7-3fm9?

GHSA-cf3q-gqg7-3fm9 affects the following packages: github.com/envoyproxy/envoy (Go), github.com/envoyproxy/envoy (Go), github.com/envoyproxy/envoy (Go), github.com/envoyproxy/envoy (Go). Ecosystems affected: Go.

How do I fix GHSA-cf3q-gqg7-3fm9?

Update github.com/envoyproxy/envoy to 1.30.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-cf3q-gqg7-3fm9 is resolved across your whole dependency graph.

How do I detect GHSA-cf3q-gqg7-3fm9 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/envoyproxy/envoy. 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.

How do I mitigate GHSA-cf3q-gqg7-3fm9 if there is no patch (or I can't update yet)?

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 does O3 Security protect against GHSA-cf3q-gqg7-3fm9?

O3 pinpoints whether GHSA-cf3q-gqg7-3fm9 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-cf3q-gqg7-3fm9 actively exploited in the wild?

No public exploit code has been indexed for GHSA-cf3q-gqg7-3fm9 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-cf3q-gqg7-3fm9?

GHSA-cf3q-gqg7-3fm9 has an EPSS (Exploit Prediction Scoring System) score of 0.4%, placing it in the 32th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

When was GHSA-cf3q-gqg7-3fm9 published, and has it been updated?

GHSA-cf3q-gqg7-3fm9 was published on March 21, 2025 and was last updated on March 25, 2025. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹 Go

GHSA-cf3q-gqg7-3fm9

MEDIUM

Envoy crashes when HTTP ext_proc processes local replies

Also known asBIT-envoy-2025-30157CVE-2025-30157

Published

Mar 21, 2025

Updated

Mar 25, 2025

Affected

4 pkgs

Patched

4 / 4

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

0.4%probability of exploitation in next 30 days

Lower Risk32th percentile+0.36%

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

4 pkgs affected

🐹github.com/envoyproxy/envoy🐹github.com/envoyproxy/envoy🐹github.com/envoyproxy/envoy🐹github.com/envoyproxy/envoy

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

Summary

Envoy's ext_proc HTTP filter is at risk of crashing if a local reply is sent to the external server due to the filter's life time issue. A known situation is the fail of a websocket handshake will trigger a local reply leading to the crash of Envoy.

PoC

If both websocket and ext_proc are enabled, a failed handshake will trigger a local reply, thus ext_proc will crash.

Mitigation

Disable websocket traffic
Change the websocket response from backend to always return 101 Switch protocol based on RFC.
Apply the patch and the ext_proc filter will not send the local reply that is generated by Envoy to the ext_proc server for processing.
Apply the patch that the router will cancel the upstream requests when sending a local reply.

Impact

Denial of service

Reporter

Vasilios Syrakis Fernando Cainelli

Affected Packages

4 total 4 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/envoyproxy/envoy`	all versions	1.30.10
🐹Go	`github.com/envoyproxy/envoy`	≥ 1.31.0&&< 1.31.6	1.31.6
🐹Go	`github.com/envoyproxy/envoy`	≥ 1.32.0&&< 1.32.4	1.32.4
🐹Go	`github.com/envoyproxy/envoy`	≥ 1.33.0&&< 1.33.1	1.33.1

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/envoyproxy/envoy. 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 github.com/envoyproxy/envoy to 1.30.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-cf3q-gqg7-3fm9 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-cf3q-gqg7-3fm9 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-cf3q-gqg7-3fm9. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Summary Envoy's ext_proc HTTP filter is at risk of crashing if a local reply is sent to the external server due to the filter's life time issue. A known situation is the fail of a websocket handshake will trigger a local reply leading to the crash of Envoy. ### PoC If both websocket and ext_proc are enabled, a failed handshake will trigger a local reply, thus ext_proc will crash. ### Mitigation 1. Disable websocket traffic 2. Change the websocket response from backend to always return `101 Switch protocol` based on RFC. 3. Apply the patch and the ext_proc filter will not send the local r

O3 Security · Impact-Aware SCA

Is GHSA-cf3q-gqg7-3fm9 in your dependencies?

O3 detects GHSA-cf3q-gqg7-3fm9 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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