CVE-2026-28446
Published: 05 March 2026
Summary
CVE-2026-28446 is a critical-severity Incorrect Implementation of Authentication Algorithm (CWE-303) vulnerability in Openclaw Openclaw. Its CVSS base score is 9.2 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 46.4th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified are NIST 800-53 AC-3 (Access Enforcement) and IA-8 (Identification and Authentication (Non-organizational Users)).
Deeper analysis
CVE-2026-28446 is an authentication bypass vulnerability in OpenClaw versions prior to 2026.2.1 when the voice-call extension is installed and enabled. The flaw occurs in inbound allowlist policy validation, which incorrectly accepts empty caller IDs and performs suffix-based matching instead of strict equality checks. Published on 2026-03-05, it carries a CVSS v3.1 base score of 9.4 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L) and is associated with CWE-303.
Remote, unauthenticated attackers can exploit this vulnerability over the network with low complexity and no user interaction. By placing calls with missing caller IDs or phone numbers ending in allowlisted digits, they bypass inbound access controls, gain access to the voice-call agent, and execute arbitrary tools.
Advisories recommend upgrading to OpenClaw 2026.2.1 or later to mitigate the issue. Relevant resources include the fixing GitHub commit at https://github.com/openclaw/openclaw/commit/f8dfd034f5d9235c5485f492a9e4ccc114e97fdb, the GitHub Security Advisory at https://github.com/openclaw/openclaw/security/advisories/GHSA-4rj2-gpmh-qq5x, and the Vulncheck advisory at https://www.vulncheck.com/advisories/openclaw-inbound-allowlist-policy-bypass-in-voice-call-extension-via-empty-caller-id.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-9896
Vulnerability details
OpenClaw versions prior to 2026.2.1 with the voice-call extension installed and enabled contain an authentication bypass vulnerability in inbound allowlist policy validation that accepts empty caller IDs and uses suffix-based matching instead of strict equality. Remote attackers can bypass inbound…
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access controls by placing calls with missing caller IDs or numbers ending with allowlisted digits to reach the voice-call agent and execute tools.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
The vulnerability is an authentication bypass in a public-facing voice-call service (AV:N/PR:N), enabling remote unauthenticated exploitation to execute arbitrary tools, directly mapping to T1190: Exploit Public-Facing Application.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly addresses the authentication bypass by enforcing strict inbound allowlist policy validation with exact caller ID matching to prevent unauthorized access to the voice-call agent.
Mitigates the vulnerability by requiring validation of caller ID inputs to reject empty values and enforce strict equality instead of suffix-based matching.
Ensures non-organizational users such as remote callers are properly identified and authenticated, preventing bypass via missing or malformed caller IDs.