CVE-2026-51541
NVD analysis in progress
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.
What this means
- Exposure
- Exploitable remotely over the network, without authentication and with no action from the victim.
- Impact
- An attacker can read sensitive data and take the service offline.
- Weakness
- An out-of-bounds read exposes adjacent memory, often leftover secrets.
- Likelihood
- Its EPSS score stays low: nothing points to imminent exploitation, which is no reason to leave it unpatched.
What to doPatch without waiting for the next scheduled cycle. Start with the instances exposed to the internet.
Read automatically from the CVSS vector, the weakness type (CWE) and the EPSS score. The technical description above remains the one published by NIST.