CVE-2026-49956: nesquena Hermes WebUI profile isolation bypass in session search

CVE-2026-49956 · Severity: medium · CVSS 6.5 · Published 2026-06-09

Hermes WebUI, a web interface for managing sessions and projects, contains a security flaw where users can view data they are not authorized to see. By using the search feature, a logged-in user can bypass profile restrictions to access session titles and chat transcripts belonging to other users or profiles. This could lead to the exposure of sensitive information contained within private sessions.

Technologies: Nesquena Hermes WebUI. Vendors: Nesquena.

Quick answers

Is CVE-2026-49956 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-49956 being exploited in the wild.
How severe is CVE-2026-49956?
Medium severity, with a CVSS score of 6.5, published 9 June 2026.
Which products and versions are affected?
Nesquena Hermes WebUI < 0.51.269.
Is there a fix for CVE-2026-49956?
A patch was published on 2026-06-05: Fix merged in PR #3646 and released in v0.51.269 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-49956 attacked?
It is attacked over the network, in a web application.
Am I affected by CVE-2026-49956?
Check whether you run Nesquena Hermes WebUI at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A missing authorization check (CWE-862) in the '_handle_sessions_search' handler in 'api/routes.py' allows authenticated users to bypass profile isolation. The vulnerable component queried 'all_sessions()' directly without applying the '_profiles_match' filtering logic used by other endpoints. An attacker can send crafted requests to the '/api/sessions/search' endpoint to retrieve session metadata and transcript message content from profiles other than their own active profile. The vulnerability is resolved in version 0.51.269 by enforcing active-profile scoping by default unless an explicit aggregate opt-in is requested.

Affected products

  • nesquena Hermes WebUI < 0.51.269

Timeline

  • 2026-06-05: patched: Fix merged in PR #3646 and released in v0.51.269
  • 2026-06-09: disclosed: CVE published to NVD

References

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