Integer overflow in Opener Project
CVE-2026-51540
OpENer 2.3.0 (master branch up to commit 76b95cf) is vulnerable to a severe memory corruption issue caused by an integer underflow in the processing of connected explicit messages (SendUnitData).
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.006 (45.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 45th percentile — 45.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.006 · change: +0.001
Affected products
- Opener Project — versions 2.3.0
Weakness classification (CWE)
References
- gist.github.com/MrAlaskan/5e0c2af7f4a1d188814c7fa8f812c8da (Third Party Advisory)
- github.com/EIPStackGroup/OpENer/issues/568 (Exploit, Issue Tracking, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-51540?
- CVE-2026-51540 is a critical-severity vulnerability in Opener Project, classified under Integer Underflow. CVSS score: 9.8/10. Published 2026-07-13.
- How severe is CVE-2026-51540?
- Critical severity. CVSS v3 base score is 9.8 out of 10.