The vulnerability allows an attacker or a legitimate user to access sensitive provider API keys that were set in a previously active profile. The Hermes-WebUI environment variable loader does not clear variables from the previous profile before loading the next one, so switching profiles preserves environment state. This additive dotenv reload behavior enables cross‑profile leakage of secrets, effectively breaking the security isolation that users expect between separate profile contexts.

nesquena hermes‑webui. Versions prior to v0.50.12 (including the release tagged v0.50.11 and earlier) are vulnerable. The patch was applied in releases v0.50.12 and later, such as v0.50.132.

The CVSS score of 4.8 indicates moderate severity. EPSS is not available, so current exploitation probability is unknown, but the lack of a KEV listing suggests no known widespread exploitation. The attack can be performed by any user who can switch profiles within the same Hermes‑WebUI instance; it does not require remote code execution or elevated privileges, only the ability to load a malicious profile. The compromised credentials could then be used to access downstream services or sensitive data.