RCE in Openbullet Openbullet2
CVE-2026-25856
OpenBullet2 through version 0.3.2 contains an authenticated remote code execution vulnerability that allows authenticated users to execute arbitrary C# code on the server host by creating or modifying job configurations. Attackers can leverage the plain C# execution mode, which lacks reference filtering or API restrictions, to access the file system, spawn processes, and invoke arbitrary .NET APIs as the process user.
Vulnerability class: RCE (Remote Code Execution)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.009 (57.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 58th percentile — 57.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.009 · change: +0.004
Affected products
- Openbullet Openbullet2 — versions 0
Weakness classification (CWE)
References
- hackernoon.com/one-empty-header-to-admin-how-an-auth-bypass-breaks-openbullet2 (technical-description, exploit)
- www.vulncheck.com/advisories/openbullet2-authenticated-rce-via-job-configuratio… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-25856?
- CVE-2026-25856 is a high-severity vulnerability in Openbullet Openbullet2, classified under Code Injection. CVSS score: 8.8/10. Published 2026-06-08.
- How severe is CVE-2026-25856?
- High severity. CVSS v3 base score is 8.8 out of 10.