Envoy up to 1.31.7/1.32.5/1.33.2/1.34.0 URI Template Matcher restrictive regex

Summaryinfo

A vulnerability classified as problematic has been found in Envoy up to 1.31.7/1.32.5/1.33.2/1.34.0. This issue affects some unknown processing of the component URI Template Matcher. Performing a manipulation results in restrictive regex. This vulnerability is identified as CVE-2025-46821. The attack can be initiated remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in Envoy up to 1.31.7/1.32.5/1.33.2/1.34.0. This affects some unknown processing of the component URI Template Matcher. The manipulation with an unknown input leads to a restrictive regex vulnerability. CWE is classifying the issue as CWE-186. A regular expression is overly restrictive, which prevents dangerous values from being detected. This is going to have an impact on confidentiality. The summary by CVE is:

Envoy is a cloud-native edge/middle/service proxy. Prior to versions 1.34.1, 1.33.3, 1.32.6, and 1.31.8, Envoy's URI template matcher incorrectly excludes the `*` character from a set of valid characters in the URI path. As a result URI path containing the `*` character will not match a URI template expressions. This can result in bypass of RBAC rules when configured using the `uri_template` permissions. This vulnerability is fixed in Envoy versions v1.34.1, v1.33.3, v1.32.6, v1.31.8. As a workaround, configure additional RBAC permissions using `url_path` with `safe_regex` expression.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2025-46821 since 04/30/2025. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 1.31.8, 1.32.6, 1.33.3 or 1.34.1 eliminates this vulnerability.

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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
• 1.31.0
• 1.31.1
• 1.31.2
• 1.31.3
• 1.31.4
• 1.31.5
• 1.31.6
• 1.31.7
• 1.32
• 1.32.0
• 1.32.1
• 1.32.2
• 1.32.3
• 1.32.4
• 1.32.5
• 1.33
• 1.33.0
• 1.33.1
• 1.33.2
• 1.34.0

License

• free

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

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