Vulnerability-Lookup

GHSA-34J3-4JPJ-GX6Q

Vulnerability from github – Published: 2026-06-17 21:34 – Updated: 2026-06-17 21:34

Details

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.

Severity

6.5 (Medium)


                  
                    CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

7.1 (High)


                  
                    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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-55198"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-639"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-17T19:18:13Z",
    "severity": "HIGH"
  },
  "details": "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.",
  "id": "GHSA-34j3-4jpj-gx6q",
  "modified": "2026-06-17T21:34:38Z",
  "published": "2026-06-17T21:34:38Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-55198"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nesquena/hermes-webui/pull/3991"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nesquena/hermes-webui/pull/4269"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nesquena/hermes-webui/commit/2a3baa71b81ca92da8ece8616a09f15894beec71"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nesquena/hermes-webui/releases/tag/v0.51.443"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/hermes-webui-cross-profile-session-data-exfiltration-via-session-export-endpoint"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-55198 (GCVE-0-2026-55198)

Vulnerability from cvelistv5 – Published: 2026-06-17 17:59 – Updated: 2026-07-14 21:33 X_Open Source

Title

Hermes WebUI < 0.51.443 - Cross-Profile Session Data Exfiltration via Session Export Endpoint

Summary

Severity

7.1 (High)


                        
                          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)


                        
                          CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-17 19:30 UTC

CWE

CWE-639 - Authorization Bypass Through User-Controlled Key

Assigner

VulnCheck mitre root

References

5 references

URL	Tags
https://github.com/nesquena/hermes-webui/releases…	release-notes
https://github.com/nesquena/hermes-webui/pull/3991	issue-tracking
https://github.com/nesquena/hermes-webui/pull/4269	issue-tracking
https://github.com/nesquena/hermes-webui/commit/2…	patch
https://www.vulncheck.com/advisories/hermes-webui…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
nesquena	hermes-webui	Affected: 0 , < 0.51.443 (semver) Unaffected: 0.51.443 (semver) cpe:2.3:a:get-hermes:hermes_web_ui::::::::

Date Public

2026-06-11 00:00

Credits

Chia Min Jun Lennon

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JSON

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.