CVE-2026-55198

MEDIUMPre-NVD 6.56.5
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to the CVSS score beside it.

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.

Triggered by: GitHub Security Advisory CVSS
Sources: the CNA's CVSS, EPSS, GitHub Security Advisory
Trending — 3 sources updated this weekElevated
6.5EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (the SSVC decision on this page).
  • CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
CISA-KEV: Not listedEPSS PROB: 0.5%CVSS: 6.5Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

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.

CVSS v3
6.5
EG Score
6.5MEDIUMmedium confidence
EG Risk
45
EG Risk 45/100

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 computed (value × EchelonGraph’s weight)
Severity65% × 45%
The EG Score, 6.5 of 10.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Track* at high (mission-essential systems).
Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.5%
EPSS %ILE
39th
KEV
Not listed

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines.

Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

June 17, 2026

Last Modified

September 17, 2026

Advisory Details (5)

Auto-updated Jun 17, 2026
Patch available. Sources: github_commit, github_pr, github_release.
GitHub pull request

[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/3991
Web page

Hermes 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-endpoint
GitHub release Patch Available

v0.51.443

Patch available: nesquena/hermes-webui v0.51.443

https://github.com/nesquena/hermes-webui/releases/tag/v0.51.443
GitHub pull request Patch Available

Release 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/4269
GitHub commit Patch Available

commit 2a3baa71b81c (nesquena/hermes-webui)

Patch available: nesquena/hermes-webui v0.51.452 (contains commit 2a3baa71b81c)

https://github.com/nesquena/hermes-webui/commit/2a3baa71b81ca92da8ece8616a09f15894beec71

Vendor 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 11× in last 7d / 34× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 100 of 215 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 115 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-11 19:39 UTCEG score recompute
  2. 2026-10-11 16:54 UTCEG score recompute
  3. 2026-10-11 14:17 UTCEG score recompute
  4. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  5. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  6. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  7. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  8. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  9. 2026-10-07 13:05 UTCOSV refresh
  10. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  11. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  12. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  13. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  14. 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  15. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  16. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  17. 2026-09-29 15:22 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  18. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  19. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  20. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  21. 2026-09-24 14:04 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  22. 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  23. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  24. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  25. 2026-09-17 19:31 UTCEPSS rescoreEPSS 0.3% · 19th percentile
Show 75 more
  1. 2026-09-17 19:11 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  2. 2026-09-17 18:17 UTCEG score recompute
  3. 2026-09-17 18:16 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  4. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  5. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  6. 2026-09-15 03:11 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  7. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  8. 2026-09-13 14:07 UTCEG score recompute
  9. 2026-09-13 14:07 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  10. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  11. 2026-09-10 09:35 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  12. 2026-09-08 22:01 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  13. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  14. 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  15. 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  16. 2026-09-01 13:54 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  17. 2026-09-01 04:40 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  18. 2026-08-30 21:16 UTCEG score recompute
  19. 2026-08-30 21:16 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  20. 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  21. 2026-08-30 01:22 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  22. 2026-08-28 21:41 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  23. 2026-08-27 14:25 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  24. 2026-08-26 14:46 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  25. 2026-08-25 13:49 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  26. 2026-08-25 04:29 UTCEG score recompute
  27. 2026-08-25 04:29 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  28. 2026-08-24 05:18 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  29. 2026-08-23 03:57 UTCEG score recompute
  30. 2026-08-23 03:57 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  31. 2026-08-23 00:19 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  32. 2026-08-21 23:49 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  33. 2026-08-21 07:23 UTCEG score recompute
  34. 2026-08-21 07:23 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  35. 2026-08-20 22:55 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  36. 2026-08-20 08:12 UTCEG score recompute
  37. 2026-08-20 08:12 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  38. 2026-08-19 17:04 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  39. 2026-08-19 08:08 UTCEG score recompute
  40. 2026-08-19 08:08 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  41. 2026-08-18 13:48 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  42. 2026-08-17 13:47 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  43. 2026-08-16 17:08 UTCEG score recompute
  44. 2026-08-16 17:08 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  45. 2026-08-16 14:56 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  46. 2026-08-16 02:14 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  47. 2026-08-15 17:57 UTCEG score recompute
  48. 2026-08-15 17:57 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  49. 2026-08-15 01:30 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  50. 2026-08-14 18:46 UTCEG score recompute
  51. 2026-08-14 18:46 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  52. 2026-08-13 22:00 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  53. 2026-08-13 19:34 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  54. 2026-08-12 20:23 UTCEG score recompute
  55. 2026-08-12 20:23 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  56. 2026-08-12 13:51 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  57. 2026-08-11 21:12 UTCEG score recompute
  58. 2026-08-11 21:12 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  59. 2026-08-11 00:00 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  60. 2026-08-10 22:01 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  61. 2026-08-09 22:50 UTCEG score recompute
  62. 2026-08-09 22:50 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  63. 2026-08-09 13:46 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  64. 2026-08-08 23:39 UTCEG score recompute
  65. 2026-08-08 23:39 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  66. 2026-08-08 16:37 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  67. 2026-08-08 00:28 UTCEG score recompute
  68. 2026-08-08 00:28 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  69. 2026-08-07 01:16 UTCEG score recompute
  70. 2026-08-07 01:16 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  71. 2026-08-06 13:47 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  72. 2026-08-06 02:05 UTCEG score recompute
  73. 2026-08-06 02:05 UTCGHSA enrichmentGHSA-34j3-4jpj-gx6q · GitHub severity HIGH · GitHub CVSS 6.5
  74. 2026-08-05 19:17 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  75. 2026-08-05 02:54 UTCEG score recompute

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-55198?
CVE-2026-55198 is a medium-severity vulnerability; its CVE record was published on June 17, 2026. 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 handlesession_export handler in api/routes.py fails to verify active-profile ownership before serializing session…
When was CVE-2026-55198 made public?
CVE-2026-55198 was made public on June 11, 2026: that is the date its CVE record's CNA, VulnCheck, gives for when the vulnerability was made public. The CVE record itself was published on June 17, 2026. EchelonGraph's copy of the record carries a last-modified date of September 17, 2026; the record at its source may have been updated since.
Is CVE-2026-55198 actively exploited?
CVE-2026-55198 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.5% probability of exploitation in the next 30 days (39th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-55198?
CVE-2026-55198 has a CVSS base score of 6.5 (the CNA's own assessment, by vulncheck; NVD's own analysis pending).
How do I remediate CVE-2026-55198?
A fix for CVE-2026-55198 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-55198 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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