envoyproxy envoy up to 1.34.12/1.35.8/1.36.4/1.37.0 apply_on_stream_done use after free

Summaryinfo

A vulnerability marked as critical has been reported in envoyproxy envoy up to 1.34.12/1.35.8/1.36.4/1.37.0. This affects the function apply_on_stream_done. The manipulation leads to use after free. This vulnerability is referenced as CVE-2026-26330. Remote exploitation of the attack is possible. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in envoyproxy envoy up to 1.34.12/1.35.8/1.36.4/1.37.0. This issue affects the function apply_on_stream_done. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is availability. The summary by CVE is:

Envoy is a high-performance edge/middle/service proxy. Prior to 1.37.1, 1.36.5, 1.35.8, and 1.34.13, At the rate limit filter, if the response phase limit with apply_on_stream_done in the rate limit configuration is enabled and the response phase limit request fails directly, it may crash Envoy. When both the request phase limit and response phase limit are enabled, the safe gRPC client instance will be re-used for both the request phase request and response phase request. But after the request phase request is done, the inner state of the request phase limit request in gRPC client is not cleaned up. When a second limit request is sent at response phase, and the second limit request fails directly, the previous request's inner state may be accessed and result in crash. This vulnerability is fixed in 1.37.1, 1.36.5, 1.35.8, and 1.34.13.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-26330 since 02/13/2026. The exploitation is known to be difficult. The attack may be initiated remotely. Technical details are known, but no exploit is available.

Upgrading to version 1.34.13, 1.35.9, 1.36.5 or 1.37.1 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-0704). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

• Google Cloud Platform

Productinfo

Type

• Firewall Software

Vendor

• envoyproxy

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
• 1.34
• 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
• 1.34.9
• 1.34.10
• 1.34.11
• 1.34.12
• 1.35
• 1.35.0
• 1.35.1
• 1.35.2
• 1.35.3
• 1.35.4
• 1.35.5
• 1.35.6
• 1.35.7
• 1.35.8
• 1.36
• 1.36.0
• 1.36.1
• 1.36.2
• 1.36.3
• 1.36.4
• 1.37.0

License

• free

Website

• Product: https://github.com/envoyproxy/envoy/

CPE 2.3info

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CPE 2.2info

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Entryinfo

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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