CVE-2025-64527

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

E

nvoy is a high-performance edge/middle/service proxy. In 1.33.12, 1.34.10, 1.35.6, 1.36.2, and earlier, 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. 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.

References

Link	Resource
https://github.com/envoyproxy/envoy/security/advisories/GHSA-mp85-7mrq-r866	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:envoyproxy:envoy::::::::
	cpe:2.3:a:envoyproxy:envoy::::::::
	cpe:2.3:a:envoyproxy:envoy::::::::
	cpe:2.3:a:envoyproxy:envoy::::::::

History

05 Dec 2025, 16:56

Type	Values Removed	Values Added
References	~~() https://github.com/envoyproxy/envoy/security/advisories/GHSA-mp85-7mrq-r866 -~~	() https://github.com/envoyproxy/envoy/security/advisories/GHSA-mp85-7mrq-r866 - Exploit, Vendor Advisory
CPE		cpe:2.3:a:envoyproxy:envoy::::::::
First Time		Envoyproxy envoy Envoyproxy

03 Dec 2025, 18:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-12-03 18:15

Updated : 2025-12-05 16:56

NVD link : CVE-2025-64527

Mitre link : CVE-2025-64527

CVE.ORG link : CVE-2025-64527

JSON object : View

Products Affected

envoy

CWE

CWE-476

NULL Pointer Dereference

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