CVE-2026-51540

CRITICAL
Published Jul 13, 2026 Modified Jul 14, 2026 CWE-191

Description

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).

Is your site exposed to CVE-2026-51540?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

9.8
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0016
Probability of exploitation
0.05%
Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-191 CWE-191

References

Frequently Asked Questions

What is 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). It has a CVSS v3.1 base score of 9.8 (CRITICAL).
How severe is CVE-2026-51540? +
CVE-2026-51540 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately. The EPSS score is 0.0016, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-51540? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2025-59368

An integer underflow vulnerability has been identified in Aicloud. An authenticated attacker may trigger this vulnerability by sending a crafted …
CVE-2025-65092

ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. In versions 5.5.1, 5.4.3, and 5.3.4, when the ESP32-P4 uses …
CVE-2026-43916

pam_authnft is a PAM session module binding nftables firewall rules to authenticated sessions via cgroupv2 inodes. Prior to 0.2.0-alpha, a …
CVE-2026-30803

Integer Underflow (Wrap or Wraparound) vulnerability in RTI Connext Micro (Core Libraries) allows Overread Buffers.This issue affects Connext Micro: from …
CVE-2024-0808 9.8

Integer underflow in WebUI in Google Chrome prior to 121.0.6167.85 allowed a remote attacker to potentially exploit heap corruption via …
CVE-2024-23313 9.8

An integer underflow vulnerability exists in the sopen_FAMOS_read functionality of The Biosig Project libbiosig 2.5.0 and Master Branch (ab0ee111). A …

Don't wait for an exploit

Scan your website for vulnerabilities like CVE-2026-51540 — free, no signup required.