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.
CVE-2026-55198
Score 6.5 from GitHub Security Advisory (severity: HIGH) published 2026-06-17. the CNA's CVSS baseline 6.5; sources differ by 0.0.
- Lower severity and no public exploit yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 6.5
- EG Score
- 6.5(medium)
- EG Risk
- 45(Track)EG Risk 45/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity65% × 45%Exploitation40% × 40%Automatability0% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 19%
- KEV
- Not listed
Published
June 17, 2026
Last Modified
July 14, 2026
Advisory Details (5)
Auto-updated Jun 17, 2026[security] fix(session): scope exports to active profile
Upstream fix in progress (PR #3991 · nesquena/hermes-webui, state=closed)
https://github.com/nesquena/hermes-webui/pull/3991Hermes WebUI < 0.51.443 - Cross-Profile Session Data Exfiltration via Session Export Endpoint | Advisories | VulnCheck
https://www.vulncheck.com/advisories/hermes-webui-cross-profile-session-data-exfiltration-via-session-export-endpointv0.51.443
Patch available: nesquena/hermes-webui v0.51.443
https://github.com/nesquena/hermes-webui/releases/tag/v0.51.443Release PD (v0.51.443): [security] scope session by-id reads + exports to active profile (#3982, #3991)
Patch available: nesquena/hermes-webui v0.51.452 (PR #4269 merged 2026-06-15)
https://github.com/nesquena/hermes-webui/pull/4269commit 2a3baa71b81c (nesquena/hermes-webui)
Patch available: nesquena/hermes-webui v0.51.452 (contains commit 2a3baa71b81c)
https://github.com/nesquena/hermes-webui/commit/2a3baa71b81ca92da8ece8616a09f15894beec71Vendor Advisories for CVE-2026-55198(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 12× in last 7d / 70× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
Showing the most recent 100 of 168 total refreshes for this CVE.
- 2026-08-27 14:25 UTCEPSS rescore
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- 2026-08-15 17:57 UTCGHSA enrichment
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Related CVEs(same CWE)
Same CWE
10 shownCWE-639
- CVE-2018-25270EG 9.8CRITICAL
- CVE-2017-20223EG 9.8CRITICAL
- CVE-2019-25487EG 9.8EPSS p94CRITICAL
- CVE-2019-25235EG 9.8CRITICAL
- CVE-2019-15310EG 9.8EPSS p94CRITICAL
- CVE-2019-15913EG 9.8CRITICAL
- CVE-2019-16340EG 9.8EPSS p97CRITICAL
- CVE-2019-13360EG 9.8EPSS p98CRITICAL
- CVE-2019-12866EG 9.8CRITICAL
- CVE-2019-9756EG 9.8CRITICAL
Frequently asked(5)
What is CVE-2026-55198?
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Dependency Blast Radius
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