CVE-2026-31848: Nexxtsolutions NEBULA300PLUS Firmware

Critical severity, CVSS 9.8. EPSS: 0.5% chance of exploitation in the next 30 days.

Nexxt Solutions Nebula 300+ firmware through version 12.01.01.37 uses the ecos_pw cookie for authentication, which contains Base64-encoded credential data combined with a static suffix. Because the encoding is reversible and lacks integrity protection, an attacker can reconstruct or forge a valid cookie value without proper authentication.

Affected products

• Nexxtsolutions NEBULA300PLUS Firmware: up to and including 12.01.01.37

Published 2026-03-23. Last modified 2026-08-10.