Auth bypass in Nullclaw Nullhub
CVE-2026-110616
NullHub through 2026.5.29 contains a missing authentication vulnerability that allows unauthenticated attackers to access the /api/* management API because the auth_token field defaults to null and is never assigned. Attackers sending requests without Authorization or Origin headers to non-loopback listeners can control agent instances, rewrite configurations including provider credentials, and manage cron jobs and MCP servers.
Vulnerability class: Broken Authentication
Published .
CVSS v3 metric
CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- hackmd.io/@1ExmmukzRMWN7B4gQ4W-4Q/rJrLma3izg (third-party-advisory)
- github.com/nullclaw/nullhub/blob/v2026.5.29/src/server.zig (technical-description)
- github.com/nullclaw/nullhub/blob/v2026.5.29/src/api/settings.zig (technical-description)
- github.com/nullclaw/nullhub/blob/v2026.5.29/Dockerfile (technical-description)
- github.com/nullclaw/nullhub (product)
- www.vulncheck.com/advisories/nullhub-through-2026.5.29-missing-authentication-f… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-110616?
- CVE-2026-110616 is a high-severity vulnerability in Nullclaw Nullhub, classified under Missing Authentication for Critical Function. CVSS score: 8.1/10. Published 2026-10-14.
- How severe is CVE-2026-110616?
- High severity. CVSS v3 base score is 8.1 out of 10.