Is this vulnerability remotely exploitable?

Yes. Any remote client capable of sending HTTP requests to an Envoy-protected endpoint can potentially exploit this issue by crafting requests with duplicate headers that target RBAC header checks.

What level of access does an attacker need to exploit this?

The attacker only needs network access to an Envoy listener using the RBAC filter. No prior authentication is required if the RBAC policy is the primary access control mechanism for that endpoint.

What is the safest general fix pattern?

The safest approach is to ensure that authorization decisions operate on the actual set of header values, not a lossy concatenated representation. Policies should be evaluated per header value or requests with unexpected duplicate security-sensitive headers should be rejected outright, aligning the implementation with the policy author's intent.

Severity:

HIGH RISK

(7.5)

Authorization Bypass via Header Concatenation (CWE-863) in Envoy RBAC Filter

CVE-2026-26308

Published:

Mar 10, 2026

Status:

Analyzed

Summary

Affected Context

Exploit Preconditions

Why This Happens

Potential Impact

General Mitigation Guidance

How Teams Detect Issues Like This

Frequently Asked Questions

Source

NDV

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May 6, 2026

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HIGH RISK

HIGH

(8.8)

Authorization Bypass (CWE-863) in OpenClaw Matrix Room Control Commands

Privilege Escalation via Bypassed Access Control

May 6, 2026

Vulnerability Type

Category:

Authorization Bypass

CWE:

CWE-863

Impact:

Bypass of RBAC Deny Rules and Unauthorized Access

Severity:

HIGH RISK

(7.5)

CVSS Version:

3.1

Vulnerability Type

Category:

Authorization Bypass

CWE:

CWE-863

Impact:

Bypass of RBAC Deny Rules and Unauthorized Access

Severity:

HIGH RISK

(7.5)

CVSS Version:

3.1

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Authorization Bypass via Header Concatenation (CWE-863) in Envoy RBAC Filter

Summary

Affected Context

Exploit Preconditions

Why This Happens

Potential Impact

General Mitigation Guidance

How Teams Detect Issues Like This

Frequently Asked Questions

Source

Recent Vulnerabilities

HIGH RISK

HIGH

(8.6)

Server-Side Request Forgery (CWE-918) in OpenClaw Zalo Plugin sendPhoto

HIGH RISK

HIGH

(8.8)

Authorization Bypass (CWE-863) in OpenClaw Matrix Room Control Commands

Vulnerability Type

Vulnerability Type

Vulnerability Type

Catch This CVE While Code Is Being Written

Ship clean & secure code faster

Ship clean & secure code faster

Ship clean & secure code faster

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