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Vulnerability record · CVE-2026-25555 · published 8 June 2026

CVE-2026-25555: OpenBullet2 through version 0.3.2 contains an authentication bypass vulnerability in the API key authenticatio…

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.

9.3 CVSS 4.0 Critical EPSS 2.7% · top 14.5% CWE-305 · CWE-305 Deferred
9.3CVSS 4.0 base score
2.7%EPSS exploitation probability, 30 days
NoNot in CISA KEV
0Affected product versions listed by NVD
2References
23 Jul 2026Last modified by NVD

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.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:

References

LinkTags
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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Source: NIST National Vulnerability Database (record CVE-2026-25555), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.