Description
The webhook platform gateway in Nous Research Hermes Agent versions builds the session chat_id as webhook:{route_name}:{delivery_id} and re-derives the authorizing route by splitting that string, so a route name containing a ":" resolves toolset authorization to a different, higher-privileged prefix route than the one authenticated, which allows a remote attacker with the target HMAC to gain that higher-privileged route's toolsets.
References4
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 53 · as of 8 November 2026
- CWE
- CWE-863
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