CVE-2026-31848
Because the encoding is reversible and lacks integrity protection, an attacker can reconstruct or forge a valid cookie value without proper authentication.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.28%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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.
- CVSS 4.0
- 8.7 HIGHCVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.28% probability · 21th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-312
- Affected
- nexxtsolutions/nebula300plus firmware
- Source
- 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.