# CVE-2026-53871: Hermes WebUI < 0.51.368 - Profile-Scoped Authorization Bypass via Forged hermes_profile Cookie

> An authenticated attacker can forge the hermes_profile cookie to bypass authorization checks and access resources across different user profiles.

- **Severity:** High 8.6 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 17 Jun 2026
- **Updated:** 17 Sep 2026
- **Also known as:** GHSA-cpcp-57xw-48rv

## What is CVE-2026-53871?

CVE-2026-53871 is a high-severity authentication bypass vulnerability in nesquena hermes-webui, published on 17 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Hermes WebUI before 0.51.368 contains an authorization bypass vulnerability in the get_profile_cookie() function that accepts unauthenticated profile names from the hermes_profile cookie. An authenticated attacker can forge the hermes_profile cookie value to bypass profile-scoped authorization checks and access sessions, files, and resources across different profiles.

Weakness: CWE-565 (Reliance on Cookies without Validation and Integrity Checking)

## Which versions are affected by CVE-2026-53871?


## How do I fix CVE-2026-53871?

No fix has been published for CVE-2026-53871 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-53871 being exploited?

There is no known exploitation of CVE-2026-53871 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-53871 and fix it if it is affected.

What it is: CVE-2026-53871 is a high-severity authentication bypass vulnerability in nesquena hermes-webui, published on 17 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-53871 in the wild and no public exploit code.

Affected product: nesquena hermes-webui. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-53871/ (Markdown: https://insights.sbomify.com/CVE-2026-53871/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53871
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53871
- OSV: https://osv.dev/vulnerability/CVE-2026-53871

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-53871/
Summaries are generated and may contain mistakes; the official description above is the record.