Envoy up to 1.33.9/1.34.8/1.35.4/1.36.0 null pointer dereference

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6.3	$0-$5k	0.00

Summaryinfo

A vulnerability, which was classified as problematic, has been found in Envoy up to 1.33.9/1.34.8/1.35.4/1.36.0. Impacted is an unknown function. This manipulation causes null pointer dereference. This vulnerability is handled as CVE-2025-62409. The attack can be initiated remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in Envoy up to 1.33.9/1.34.8/1.35.4/1.36.0. Affected by this vulnerability is an unknown functionality. 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 cloud-native, open source edge and service proxy. Prior to 1.36.1, 1.35.5, 1.34.9, and 1.33.10, large requests and responses can potentially trigger TCP connection pool crashes due to flow control management in Envoy. It will happen when the connection is closing but upstream data is still coming, resulting in a buffer watermark callback nullptr reference. The vulnerability impacts TCP proxy and HTTP 1 & 2 mixed use cases based on ALPN. This vulnerability is fixed in 1.36.1, 1.35.5, 1.34.9, and 1.33.10.

The advisory is shared at github.com. This vulnerability is known as CVE-2025-62409 since 10/13/2025. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly 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.

Upgrading to version 1.33.10, 1.34.9, 1.35.5 or 1.36.1 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (281808) and CERT Bund (WID-SEC-2025-2433). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

• Amazon Linux 2
• Google Cloud Platform

Productinfo

Name

• Envoy

Version

• 1.0
• 1.1
• 1.2
• 1.3
• 1.4
• 1.5
• 1.6
• 1.7
• 1.8
• 1.9
• 1.10
• 1.11
• 1.12
• 1.13
• 1.14
• 1.15
• 1.16
• 1.17
• 1.18
• 1.19
• 1.20
• 1.21
• 1.22
• 1.23
• 1.24
• 1.25
• 1.26
• 1.27
• 1.28
• 1.29
• 1.30
• 1.31
• 1.32
• 1.33
• 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
• 1.34
• 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
• 1.35
• 1.35.0
• 1.35.1
• 1.35.2
• 1.35.3
• 1.35.4
• 1.36.0

License

• free

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔒

CVSSv2info

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

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
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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: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Envoy 1.33.10/1.34.9/1.35.5/1.36.1

Timelineinfo

10/13/2025 CVE reserved
10/16/2025 +3 days Advisory disclosed
10/16/2025 +0 days VulDB entry created
01/07/2026 +83 days VulDB entry last update

Sourcesinfo

Advisory: GHSA-pq33-4jxh-hgm3
Status: Confirmed

CVE: CVE-2025-62409 (🔒)
GCVE (CVE): GCVE-0-2025-62409
GCVE (VulDB): GCVE-100-328861
CERT Bund: WID-SEC-2025-2433 - Google Cloud Platform (Envoy Proxy):: Mehrere Schwachstellen ermöglichen Denial of Service

Entryinfo

Created: 10/16/2025 21:54
Updated: 01/07/2026 05:59
Changes: 10/16/2025 21:54 (67), 10/17/2025 03:34 (1), 10/30/2025 00:32 (11), 10/30/2025 03:33 (7), 01/06/2026 12:59 (2), 01/07/2026 05:59 (1)
Complete: 🔍
Cache ID: 216::103

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