CVE-2026-55198
MEDIUM Exploitation: PoC
6.5
CVSS 3.1
Description
Hermes WebUI before 0.51.443 contains an authorization bypass vulnerability in the session export endpoint that allows authenticated users to access sessions from other profiles. The _handle_session_export handler in api/routes.py fails to verify active-profile ownership before serializing session data, enabling attackers to exfiltrate foreign session transcripts by guessing or knowing session identifiers.
Metadata
Severity & Metrics
6.5
MEDIUM CVSS 3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
SSVC — CISA Coordinator
Affected products (1)
| Vendor | Product | Platform | Versions |
|---|---|---|---|
| nesquena | hermes-webui | — | 0 < 0.51.443, 0.51.443 |
Weakness (CWE)
| CWE | Source | Description |
|---|---|---|
| CWE-639 | cna | Authorization Bypass Through User-Controlled Key |
CVSS scores (2)
| Score | Severity | Version | Source | Vector |
|---|---|---|---|---|
| 7.1 | HIGH | 4.0 | cna | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N |
| 6.5 | MEDIUM | 3.1 | cna | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N |
References (5)
- Release Notes https://github.com/nesquena/hermes-webui/releases/tag/v0.51.443
- Researcher Pull Request https://github.com/nesquena/hermes-webui/pull/3991
- Maintainer Pull Request https://github.com/nesquena/hermes-webui/pull/4269
- Patch Commit https://github.com/nesquena/hermes-webui/commit/2a3baa71b81ca92da8ece8616a09f15894beec71
- https://www.vulncheck.com/advisories/hermes-webui-cross-profile-session-data-exfiltration-via-session-export-endpoint