CVE-2026-31848
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk20th percentile - higher than 20% of all known CVEs
Summary
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.
Risk Assessment
An attacker can bypass authentication and gain access to the device, potentially leading to unauthorized control over the hardware and privacy breaches.
Recommendation
Implement a secure session-based authentication mechanism with cookie signing and integrity verification. Also, update the firmware to the latest version if a patch is available.
Other vulnerabilities in Nexxt Solutions Nebula 300+
See all- CVE-2026-31847High
Hidden functionality in the /goform/setSysTools endpoint in Nexxt Solutions Nebula 300+ firmware up to version 12.01.01.37 allows remote enablement of a Telnet service. An authenticated attacker can send a crafted POST request with parameters such as telnetManageEn=true and telnetPwd to activate Telnet on port 23.
- CVE-2026-31846Medium
Missing authentication in the /goform/ate endpoint in Nexxt Solutions Nebula 300+ firmware through version 12.01.01.37 allows an adjacent unauthenticated attacker to retrieve sensitive device information, including the administrator password. An attacker can decode this value to obtain valid administrative credentials and authenticate to the device.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS