CVE-2026-12495

Mercusys MB115-4GVulnerabilityCVSS 9.2

Denial-of-service (DoS) vulnerability due to a stack buffer overflow in the http_gdpr_decrypt function of the Mercusys MB115-4G device's web interface. An unauthenticated attacker could exploit this vulnerability by sending a specially crafted request to the /cgi/login endpoint, causing memory corruption and the httpd process to crash, resulting in a denial of service for the web administration service.

No public exploitation has been reported so far. No distribution fix is listed yet; apply vendor mitigations and monitor.

Recommended action: Track your distribution's security tracker and apply the fix as soon as it ships.

CVE-2026-12495 Mercusys MB115-4G Vulnerability

Severity metrics

CVSS 4.0 : 9.2 CRITICAL

Attack vectorNetwork (remote)

Attack complexityLow

Attack requirementsPresent

Privileges requiredNone

User interactionNone

Confidentiality impactHigh

Integrity impactHigh

Availability impactHigh

Subsequent confidentialityNone

Subsequent integrityNone

Subsequent availabilityNone

Vector: AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Affected & fixed versions by distribution

Versions are the native distribution strings (backport-aware): RHEL/Debian/SUSE backport fixes, so compare with the distro version comparator (dpkg / rpm / vercmp), not the upstream version.

No affected package in the tracked watchlist yet (Debian, Ubuntu, Arch, SUSE, Red Hat...). Triage may still be pending.

Sources

Advisory NVD CVE.org

Published 2026-07-27 · source: NVD