Envoy up to 1.33.12/1.34.10/1.35.6/1.36.2 onJwksError null pointer dereference

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5.4	$0-$5k	0.00

Summaryinfo

A vulnerability was found in Envoy up to 1.33.12/1.34.10/1.35.6/1.36.2. It has been rated as problematic. Affected is the function onJwksError. This manipulation causes null pointer dereference. This vulnerability is handled as CVE-2025-64527. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability has been found in Envoy up to 1.33.12/1.34.10/1.35.6/1.36.2 and classified as problematic. Affected by this vulnerability is the function onJwksError. The manipulation with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is CWE-476. 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. As an impact it is known to affect availability. The summary by CVE is:

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.

The advisory is shared at github.com. This vulnerability is known as CVE-2025-64527 since 11/05/2025. The exploitation appears to be easy. The attack can be launched remotely. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 281808 (Amazon Linux 2 : ecs-service-connect-agent, --advisory ALAS2ECS-2025-093 (ALASECS-2025-093)), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Tenable (281808) and EUVD (EUVD-2025-201100). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

• Envoy

Version

• 1.33.0
• 1.33.1
• 1.33.2
• 1.33.3
• 1.33.4
• 1.33.5
• 1.33.6
• 1.33.7
• 1.33.8
• 1.33.9
• 1.33.10
• 1.33.11
• 1.33.12
• 1.34.0
• 1.34.1
• 1.34.2
• 1.34.3
• 1.34.4
• 1.34.5
• 1.34.6
• 1.34.7
• 1.34.8
• 1.34.9
• 1.34.10
• 1.35.0
• 1.35.1
• 1.35.2
• 1.35.3
• 1.35.4
• 1.35.5
• 1.35.6
• 1.36.0
• 1.36.1
• 1.36.2

License

• free

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.4

VulDB Base Score: 4.3
VulDB Temp Score: 4.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector (GitHub_M): 🔒

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 281808
Nessus Name: Amazon Linux 2 : ecs-service-connect-agent, --advisory ALAS2ECS-2025-093 (ALASECS-2025-093)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

11/05/2025 CVE reserved
12/03/2025 +28 days Advisory disclosed
12/03/2025 +0 days VulDB entry created
01/06/2026 +34 days VulDB entry last update

Sourcesinfo

Advisory: GHSA-mp85-7mrq-r866
Status: Confirmed

CVE: CVE-2025-64527 (🔒)
GCVE (CVE): GCVE-0-2025-64527
GCVE (VulDB): GCVE-100-334201
EUVD: 🔒

Entryinfo

Created: 12/03/2025 23:37
Updated: 01/06/2026 12:59
Changes: 12/03/2025 23:37 (62), 12/05/2025 21:50 (1), 01/06/2026 12:59 (2)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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