CVE-2026-25555: OpenBullet2 0.3.2 Authentication Bypass via X-Api-Key Header

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.8% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-06-08 · updated 2026-07-23
Weakness: CWE-305

Description

OpenBullet2 through version 0.3.2 contains an authentication bypass vulnerability in the API key authentication middleware that allows unauthenticated attackers to gain admin access by supplying an empty X-Api-Key header value. Attackers can exploit the middleware's comparison of the supplied header against an empty AdminApiKey default string to access the admin console and all API endpoints without valid credentials.

Affected products

openbullet2: through 0.3.2

References

https://hackernoon.com/one-empty-header-to-admin-how-an-auth-bypass-breaks-openbullet2
https://www.vulncheck.com/advisories/openbullet2-authentication-bypass-via-x-api-key-header

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