SecuriTricks - CVE-2025-64527

Description

Envoy 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.

Product(s) Impacted

Vendor	Product	Versions
Envoy	Envoy	<1.36.2

Weaknesses

Common security weaknesses mapped to this vulnerability.

CWE-476

NULL Pointer Dereference

A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit.

*CPE(s)

Affected systems and software identified for this CVE.

Type	Vendor	Product	Version	Update	Edition	Language	Software Edition	Target Software	Target Hardware	Other Information
a	envoy	envoy	<1.36.2	/	/	/	/	/	/	/

References

https://github.com/envoyproxy/envoy/security/advisories/GHSA-mp85-7mrq-r866

CVSS Score

6.5 / 10

CVSS Data - 3.1

Attack Vector: NETWORK
Attack Complexity: LOW
Privileges Required: LOW
Scope: UNCHANGED
Confidentiality Impact: NONE
Integrity Impact: NONE
Availability Impact: HIGH

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

View Vector String

Timeline

Published: Dec. 3, 2025, 6:15 p.m.
Last Modified: Dec. 4, 2025, 5:15 p.m.

Status : Undergoing Analysis

CVE has been recently published to the CVE List and has been received by the NVD.

More info

Source

security-advisories@github.com

CVE-2025-64527