Is CVE-2026-53871 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-53871 being exploited in the wild.

How severe is CVE-2026-53871?

High severity, with a CVSS score of 8.1, published 17 June 2026.

Which products and versions are affected?

nesquena Hermes WebUI < 0.51.368.

Is there a fix for CVE-2026-53871?

A patch was published on 2026-06-12: Fix merged in version 0.51.368 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-53871 attacked?

It is attacked over the network, in a web application.

Am I affected by CVE-2026-53871?

Check whether anything you run is named in the advisory. 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.

CVE-2026-53871: Nesquena Hermes WebUI authorization bypass in get_profile_cookie

Q: Is there a fix for CVE-2026-53871?

A patch was published on 2026-06-12: Fix merged in version 0.51.368 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-53871 attacked?

It is attacked over the network, in a web application.

Q: Am I affected by CVE-2026-53871?

Check whether anything you run is named in the advisory. 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.

CVE-2026-53871 · Severity: high · CVSS 8.1 · Published 2026-06-17

Hermes WebUI, a web-based interface for managing data profiles and sessions, contains a security flaw in how it handles user profiles. An authenticated user can manipulate their browser cookies to trick the system into granting them access to data, files, and sessions belonging to other profiles. This could lead to unauthorized access to sensitive information or the ability to modify data across different workspaces or tenants.

Quick answers

Is CVE-2026-53871 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-53871 being exploited in the wild.
How severe is CVE-2026-53871?: High severity, with a CVSS score of 8.1, published 17 June 2026.
Which products and versions are affected?: nesquena Hermes WebUI < 0.51.368.
Is there a fix for CVE-2026-53871?: A patch was published on 2026-06-12: Fix merged in version 0.51.368 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-53871 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2026-53871?: Check whether anything you run is named in the advisory. 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

An authorization bypass exists in the `get_profile_cookie()` function within Hermes WebUI. The application relies on the `hermes_profile` cookie to determine the active profile context for profile-scoped routes and visibility guards. Because this cookie was not cryptographically bound to the user's session or authenticated on the server side, an attacker with valid credentials can manually modify the cookie value to any target profile name. This allows the attacker to bypass profile-scoped authorization checks and perform cross-profile operations on sessions, files, and resources. The fix, introduced in version 0.51.368, implements HMAC-signing of the profile cookie bound to the session token.

Affected products

nesquena Hermes WebUI < 0.51.368

Timeline

2026-06-12: patched: Fix merged in version 0.51.368
2026-06-17: disclosed: CVE published to NVD

References

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