Description
KAYSUS KS-WR3600 routers with firmware 1.0.5.9.1 allow authentication bypass during session validation. If any user is logged in, endpoints such as /cgi-bin/system-tool accept unauthenticated requests with empty or invalid session values. This design flaw lets attackers piggyback on another user's active session to retrieve sensitive configuration data or execute privileged actions without authentication.
Affected products
kaysus: ks-wr3600 firmware; kaysus: ks-wr3600
References3
Metrics
- CVSS 3.1
-
9.4
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L - EPSS — exploit probability
- 1% percentile: 47 · as of 11 November 2026
- CWE
- CWE-287
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