CVE-2026-73551

medium

Envoy is an open source edge and service proxy designed for cloud-native applications.

Vendor / product: Envoyproxy — envoy

Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to 1.36.10, 1.37.6, 1.38.4, and 1.39.1, Envoy's URL normalization does not recognize dot and dotdot path segments when they carry semicolon parameters. A request such as /user/..;foo=bar/admin is therefore not canonicalized to /admin even when path normalization is enabled. If an upstream interprets the segment according to RFC 3986 while Envoy applies routing or RBAC to the uncollapsed path, a remote client can cause path confusion and bypass path-based security policy. The relevant scope boundary is that the security consequence depends on a downstream/upstream path interpretation mismatch or a path-based Envoy decision. This issue is fixed in versions 1.36.10, 1.37.6, 1.38.4, and 1.39.1.

CVSS

5.3

5.3 (CVSS v3.1)

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

Severity source: NVD CVSS v3.1 (security-advisories@github.com)

Timeline (UTC)

Published: 2026-09-21 21:17

Modified: 2026-10-05 14:06

NVD status: Analyzed

Last synced 3 days ago

Verified against the source API 2026-10-27 06:54 UTC

Exploitation

Not listed in CISA KEV (as of last catalog sync)

Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

envoyproxy / envoy <1.36.10, ≥1.37.0 <1.37.6, ≥1.38.0 <1.38.4, ≥1.39.0 <1.39.1

Weakness classification (CWE)

CWE-647

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

Vendor advisory: https://github.com/envoyproxy/envoy/security/advisories/GHSA-2w8w-rfw7-8gg4

Patch / mitigation: https://github.com/envoyproxy/envoy/commit/28b6d60a6d96edeece121cac5be701eb46cc7f24

Patch / mitigation: https://github.com/envoyproxy/envoy/commit/d40a68b0a30a003c4e0a9fd3af637f828b52c37b

Patch / mitigation: https://github.com/envoyproxy/envoy/commit/e9d6c329f9a3ff19432bf39b60c601df7e3eda33

Patch / mitigation: https://github.com/envoyproxy/envoy/commit/f74d1107c4f5c9679b66f7a03a6c5b75ddde1989

References

https://github.com/envoyproxy/envoy/commit/28b6d60a6d96edeece121cac5be701eb46cc7f24 security-advisories@github.com
https://github.com/envoyproxy/envoy/commit/d40a68b0a30a003c4e0a9fd3af637f828b52c37b security-advisories@github.com
https://github.com/envoyproxy/envoy/commit/e9d6c329f9a3ff19432bf39b60c601df7e3eda33 security-advisories@github.com
https://github.com/envoyproxy/envoy/commit/f74d1107c4f5c9679b66f7a03a6c5b75ddde1989 security-advisories@github.com
https://github.com/envoyproxy/envoy/releases/tag/v1.36.10 security-advisories@github.com
https://github.com/envoyproxy/envoy/releases/tag/v1.37.6 security-advisories@github.com
https://github.com/envoyproxy/envoy/releases/tag/v1.38.4 security-advisories@github.com
https://github.com/envoyproxy/envoy/releases/tag/v1.39.1 security-advisories@github.com
https://github.com/envoyproxy/envoy/security/advisories/GHSA-2w8w-rfw7-8gg4 security-advisories@github.com

Data sources

NVD CVE API 2.0 — fetched 2026-10-27 06:54 UTC · record ↗

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CVE-2026-73551

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