CVE-2026-90474

MEDIUMPre-NVD 6.86.8
EchelonGraph scoreMEDIUM confidence

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

Score 6.8 from GitHub Security Advisory (severity: HIGH) published 2026-09-12. The CNA's CVSS baseline 6.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: the CNA's CVSS, EPSS, GitHub Security Advisory
Elevated

Also known asEUVD-2026-76850 (ENISA EUVD) · GHSA-c47m-m826-fc8g (GitHub Security Advisories)Source: ENISA EUVD

6.8EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (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: 0.6%CVSS: 6.8Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

MCPHub before 1.0.32 contains an authentication bypass vulnerability in its embedded OAuth 2.0 authorization server where client authentication is disabled by default and PKCE enforcement is optional. Attackers who obtain an authorization code through interception can redeem it for access tokens without providing a client secret or PKCE verifier, gaining access to victim accounts and their privileges.

CVSS v3
6.8
EG Score
6.8MEDIUMmedium confidence
EG Risk
47
EG Risk 47/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity68% × 45%
Impact severity (EG Severity): CVSS 6.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.
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, Track* at medium and Attend at high mission impact.
Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (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 at low or medium mission impact and sooner than that at high.
EPSS PROB
0.6%
EPSS %ILE
46th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (6.8): severity, escalated by confirmed exploitation. This CVE's 6.8 is its impact severity (EG Severity), not escalated.

EG Severity
6.8 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.6% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-24). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track* at medium mission impactTrack at low, Track* at medium and Attend at high mission impact.CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low, Track* at medium and Attend at high mission impact.

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (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)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (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

September 12, 2026

Last Modified

September 24, 2026

Advisory Details (5)

Auto-updated Sep 12, 2026
Patch available. Sources: github, github_commit, github_release.
Web page

MCPHub before 1.0.32 OAuth 2.0 Authentication Bypass | Advisories | VulnCheck

https://www.vulncheck.com/advisories/mcphub-before-1.0.32-oauth-2.0-authentication-bypass
GitHub advisoryMentions a patch (unverified)

OAuth Authorization Server: Client Authentication Not Enforced (No PKCE, `plain` Accepted, Client Secret Skipped) — Intercepted Codes Redeemable Without Secret/Verifier · Advisory · samanhappy/mcphub · GitHub

https://github.com/samanhappy/mcphub/security/advisories/GHSA-3m7m-37xf-xp9x
GitHub release Patch Available

v1.0.32

Patch available: samanhappy/mcphub v1.0.32

https://github.com/samanhappy/mcphub/releases/tag/v1.0.32
GitHub commit Patch Available

commit e927620cd1a8 (samanhappy/mcphub)

Patch available: samanhappy/mcphub v1.0.32 (contains commit e927620cd1a8)

https://github.com/samanhappy/mcphub/commit/e927620cd1a80e8691213b01eb8cd6ffa1a66e9f
Web page

mcphub/src/services/oauthServerService.ts at v1.0.31 · samanhappy/mcphub · GitHub

https://github.com/samanhappy/mcphub/blob/v1.0.31/src/services/oauthServerService.ts#L26-L38

Vendor Advisories for CVE-2026-90474(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 8× in last 7d / 56× 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 99 of 119 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. 1 repeat row among the latest 100 is merged into the row it repeats. The 20 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-02 16:46 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  2. 2026-11-01 16:36 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  3. 2026-10-31 16:33 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  4. 2026-10-30 16:35 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  5. 2026-10-29 16:34 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  6. 2026-10-28 16:33 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  7. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  8. 2026-10-27 08:55 UTCOSV refresh
  9. 2026-10-26 16:32 UTCEPSS rescoreEPSS 0.6% · 45th percentile
  10. 2026-10-25 16:34 UTCEPSS rescoreEPSS 0.6% · 45th percentile
  11. 2026-10-25 13:52 UTCEG score recompute
  12. 2026-10-24 16:34 UTCEPSS rescoreEPSS 0.6% · 45th percentile
  13. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.6% · 45th percentile
  14. 2026-10-22 16:35 UTCEPSS rescoreEPSS 0.6% · 45th percentile
  15. 2026-10-21 16:34 UTCEPSS rescoreEPSS 0.6% · 45th percentile
  16. 2026-10-20 16:34 UTCEPSS rescoreEPSS 0.6% · 45th percentile
  17. 2026-10-19 16:33 UTCEPSS rescoreEPSS 0.6% · 45th percentile
  18. 2026-10-18 16:33 UTCEPSS rescoreEPSS 0.6% · 45th percentile
  19. 2026-10-18 03:01 UTCEG score recompute
  20. 2026-10-17 16:35 UTCEPSS rescoreEPSS 0.6% · 45th percentile
  21. 2026-10-16 16:45 UTCEPSS rescoreEPSS 0.6% · 45th percentile
  22. 2026-10-15 16:33 UTCEPSS rescoreEPSS 0.6% · 44th percentile
  23. 2026-10-14 16:34 UTCEPSS rescoreEPSS 0.6% · 44th percentile
  24. 2026-10-13 16:35 UTCEPSS rescoreEPSS 0.6% · 44th percentile
  25. 2026-10-12 16:35 UTCEPSS rescoreEPSS 0.6% · 44th percentile
Show 74 more
  1. 2026-10-12 14:46 UTCEG score recompute
  2. 2026-10-12 12:36 UTCEG score recompute
  3. 2026-10-12 12:36 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  4. 2026-10-11 22:00 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  5. 2026-10-11 19:14 UTCEG score recompute
  6. 2026-10-11 16:30 UTCEG score recompute
  7. 2026-10-11 13:50 UTCEPSS rescoreEPSS 0.6% · 44th percentile
  8. 2026-10-11 13:45 UTCEG score recompute
  9. 2026-10-10 23:05 UTCEG score recompute
  10. 2026-10-10 23:05 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  11. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.6% · 44th percentile
  12. 2026-10-09 22:15 UTCEG score recompute
  13. 2026-10-09 22:15 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  14. 2026-10-09 20:08 UTCEPSS rescoreEPSS 0.6% · 44th percentile
  15. 2026-10-08 23:08 UTCEG score recompute
  16. 2026-10-08 23:08 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  17. 2026-10-08 17:14 UTCEPSS rescoreEPSS 0.6% · 44th percentile
  18. 2026-10-08 00:05 UTCEG score recompute
  19. 2026-10-08 00:05 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  20. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.6% · 44th percentile
  21. 2026-10-07 01:12 UTCEG score recompute
  22. 2026-10-07 01:12 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  23. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.6% · 44th percentile
  24. 2026-10-06 02:19 UTCEG score recompute
  25. 2026-10-06 02:19 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  26. 2026-10-05 17:44 UTCEPSS rescoreEPSS 0.6% · 44th percentile
  27. 2026-10-05 03:12 UTCEG score recompute
  28. 2026-10-05 03:12 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  29. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.6% · 44th percentile
  30. 2026-10-04 04:05 UTCEG score recompute
  31. 2026-10-04 04:05 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  32. 2026-10-03 05:13 UTCEG score recompute
  33. 2026-10-03 05:13 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  34. 2026-10-02 06:20 UTCEG score recompute
  35. 2026-10-02 06:20 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  36. 2026-10-01 19:51 UTCEPSS rescoreEPSS 0.6% · 44th percentile
  37. 2026-10-01 07:27 UTCEG score recompute
  38. 2026-10-01 07:27 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  39. 2026-09-30 15:04 UTCEPSS rescoreEPSS 0.6% · 44th percentile
  40. 2026-09-30 08:35 UTCEG score recompute
  41. 2026-09-30 08:35 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  42. 2026-09-29 09:42 UTCEG score recompute
  43. 2026-09-29 09:42 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  44. 2026-09-28 13:52 UTCEPSS rescoreEPSS 0.6% · 44th percentile
  45. 2026-09-28 10:42 UTCEG score recompute
  46. 2026-09-28 10:42 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  47. 2026-09-27 13:49 UTCEPSS rescoreEPSS 0.6% · 43rd percentile
  48. 2026-09-27 11:45 UTCEG score recompute
  49. 2026-09-27 11:45 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  50. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.6% · 43rd percentile
  51. 2026-09-26 12:48 UTCEG score recompute
  52. 2026-09-26 12:48 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  53. 2026-09-25 13:47 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  54. 2026-09-24 14:53 UTCEG score recompute
  55. 2026-09-24 14:53 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  56. 2026-09-24 14:04 UTCEPSS rescoreEPSS 0.6% · 43rd percentile
  57. 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  58. 2026-09-23 17:22 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  59. 2026-09-23 13:01 UTCEG score recompute
  60. 2026-09-23 13:01 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  61. 2026-09-22 16:01 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  62. 2026-09-22 14:08 UTCEG score recompute
  63. 2026-09-22 14:08 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  64. 2026-09-21 21:09 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  65. 2026-09-21 15:15 UTCEG score recompute
  66. 2026-09-21 15:15 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  67. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  68. 2026-09-20 16:23 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  69. 2026-09-19 17:28 UTCEG score recompute
  70. 2026-09-19 17:28 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  71. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  72. 2026-09-18 18:35 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8
  73. 2026-09-17 19:36 UTCEG score recompute
  74. 2026-09-17 19:36 UTCGHSA enrichmentGHSA-c47m-m826-fc8g · GitHub severity HIGH · GitHub CVSS 6.8

Frequently asked(5)

What is CVE-2026-90474?
CVE-2026-90474 is a medium-severity vulnerability; its CVE record was published on September 12, 2026. MCPHub before 1.0.32 contains an authentication bypass vulnerability in its embedded OAuth 2.0 authorization server where client authentication is disabled by default and PKCE enforcement is optional. Attackers who obtain an authorization code through interception can redeem it for access tokens…
When was CVE-2026-90474 made public?
CVE-2026-90474 was made public on August 23, 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 September 12, 2026. EchelonGraph's copy of the record carries a last-modified date of September 24, 2026; the record at its source may have been updated since.
Is CVE-2026-90474 actively exploited?
CVE-2026-90474 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.6% probability of exploitation in the next 30 days (46th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-90474?
CVE-2026-90474 has a CVSS base score of 6.8 (the CNA's own assessment, by vulncheck; NVD's own analysis pending).
How do I remediate CVE-2026-90474?
A fix for CVE-2026-90474 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-90474 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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