How severe is GHSA-mp85-7mrq-r866?

GHSA-mp85-7mrq-r866 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-mp85-7mrq-r866?

GHSA-mp85-7mrq-r866 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-mp85-7mrq-r866?

Update github.com/envoyproxy/envoy to 1.36.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-mp85-7mrq-r866 is resolved across your whole dependency graph.

How do I detect GHSA-mp85-7mrq-r866 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-mp85-7mrq-r866 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-mp85-7mrq-r866?

O3 pinpoints whether GHSA-mp85-7mrq-r866 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-mp85-7mrq-r866 actively exploited in the wild?

No public exploit code has been indexed for GHSA-mp85-7mrq-r866 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-mp85-7mrq-r866?

GHSA-mp85-7mrq-r866 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 38th 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.

What type of vulnerability is GHSA-mp85-7mrq-r866?

GHSA-mp85-7mrq-r866 is classified as NULL Pointer Dereference (CWE-476). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-mp85-7mrq-r866 published, and has it been updated?

GHSA-mp85-7mrq-r866 was published on December 5, 2025 and was last updated on December 6, 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-mp85-7mrq-r866

MEDIUM

Envoy crashes when JWT authentication is configured with the remote JWKS fetching

Also known asBIT-envoy-2025-64527CVE-2025-64527

Published

Dec 5, 2025

Updated

Dec 6, 2025

Affected

4 pkgs

Patched

4 / 4

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk38th percentile+0.47%

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 crashes when JWT authentication is configured with the remote JWKS fetching, allow_missing_or_failed is enabled, multiple JWT tokens are present in the request headers and the JWKS fetch fails.

Details

This is caused by a re-entry bug in the JwksFetcherImpl. When the first token's JWKS fetch fails, onJwksError() callback triggers processing of the second token, which calls fetch() again on the same fetcher object.

The original callback's reset() then clears the second fetch's state (receiver_ and request_) which causes a crash when the async HTTP response arrives.

PoC

allow_missing_or_failed or allow_missing is enabled
The client send 2 Authorization headers
the remote JWKS fetching failed
There will be crash

Impact

DoS and Crash

Mitigation

Disable the allow_missing_or_failed or allow_missing

Affected Packages

4 total 4 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/envoyproxy/envoy`	≥ 1.36.0&&< 1.36.3	1.36.3
🐹Go	`github.com/envoyproxy/envoy`	≥ 1.35.0&&< 1.35.7	1.35.7
🐹Go	`github.com/envoyproxy/envoy`	≥ 1.34.0&&< 1.34.11	1.34.11
🐹Go	`github.com/envoyproxy/envoy`	all versions	1.33.13

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 1.36.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-mp85-7mrq-r866 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-mp85-7mrq-r866 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-mp85-7mrq-r866. 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 crashes when JWT authentication is configured with the remote JWKS fetching, `allow_missing_or_failed` is enabled, multiple JWT tokens are present in the request headers and the JWKS fetch fails. ### Details This is caused by a re-entry bug in the `JwksFetcherImpl`. When the first token's JWKS fetch fails, `onJwksError()` callback triggers processing of the second token, which calls fetch() again on the same fetcher object. The original callback's reset() then clears the second fetch's state (`receiver_ and request_`) which causes a crash when the async HTTP response arrive

O3 Security · Impact-Aware SCA

Is GHSA-mp85-7mrq-r866 in your dependencies?

O3 detects GHSA-mp85-7mrq-r866 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works