Out-of-bounds Read in Opener Project
CVE-2026-51541
OpENer 2.3.0 (commit 76b95cf) has an out-of-bounds read issue in CIP message parsing when handling malformed explicit requests with a forged EPath size. An attacker can send a valid ENIP SendRRData frame carrying a very short CIP payload whose path_size field claims that many more path words are present than are actually available. Because the parser trusts the attacker-controlled path_size and continues decoding path segments without a remaining-length boundary, it reads beyond the end of the stack receive buffer.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H.
EPSS exploit prediction
EPSS: 0.006 (44.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 44th percentile — 44.4% 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
- github.com/EIPStackGroup/OpENer/issues/582 (Exploit, Issue Tracking, Vendor Advisory)
- gist.github.com/MrAlaskan/705c680856e48c535148265c0899ad4b (Third Party Advisory)
Frequently asked questions
- What is CVE-2026-51541?
- CVE-2026-51541 is a critical-severity vulnerability in Opener Project, classified under Out-of-bounds Read. CVSS score: 9.1/10. Published 2026-07-13.
- How severe is CVE-2026-51541?
- Critical severity. CVSS v3 base score is 9.1 out of 10.