CVE-2026-8890

HIGHPre-NVD 8.28.2—
EchelonGraph scoreMEDIUM confidence

Score 8.2 from GitHub Security Advisory (severity: HIGH) published 2026-05-26. the CNA's CVSS baseline 8.2; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:vulncheck, epss, ghsa
Elevated
8.2
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 8.2Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

code100x contains an authentication bypass vulnerability in the Mobile API that allows unauthenticated attackers to impersonate arbitrary users by supplying a crafted JSON payload in the 'g' HTTP header. The middleware in middleware.ts skips identity header generation when an Auth-Key header is present without validating its value, allowing attackers to inject a spoofed user identity header that the downstream route handler in the mobile courses endpoint accepts as trusted, granting unauthorized access to course data belonging to any enrolled user or administrator.

CVSS v3
8.2
EG Score
8.2(medium)
EG Risk
68(Attend)
EG Risk 68/100SSVC: Attend

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
Severity82% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS
39.3%
KEV
Not listed

Published

May 26, 2026

Last Modified

July 23, 2026

Advisory Details (5)

Auto-updated Jun 3, 2026
No patch confirmed yet. Sources: github_pr.
github_pr

fix: prevent user ID spoofing by stripping client-supplied 'g' header in withMobileAuth

Upstream fix in progress (PR #1927 · code100x/cms, state=open)

https://github.com/code100x/cms/pull/1927
generic

bug: Mobile API - Pre -Authentication User ID Validation Bypass · Issue #1924 · code100x/cms · GitHub

https://github.com/code100x/cms/issues/1924
generic

code100x Mobile API Authentication Bypass via Header Spoofing | Advisories | VulnCheck

https://www.vulncheck.com/advisories/code100x-mobile-api-authentication-bypass-via-header-spoofing
github_pr

fix: prevent user ID spoofing by stripping client-supplied 'g' header in withMobileAuth

Upstream fix in progress (PR #1927 · code100x/cms, state=open)

https://github.com/code100x/cms/pull/1927/changes/90b489ee7c63c301107d6374d4b3f2b8e4060fe5
github_pr

fix: prevent user ID spoofing by stripping client-supplied 'g' header in withMobileAuth

Upstream fix in progress (PR #1927 · code100x/cms, state=open)

https://github.com/code100x/cms/pull/1927/changes/88c6c5e94e23da101235c4c7e9c7591ac1016549

Vendor Advisories for CVE-2026-8890(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 10× in last 7d / 43× 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 110 total refreshes for this CVE.

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

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-8890?
CVE-2026-8890 is a high vulnerability published on May 26, 2026. code100x contains an authentication bypass vulnerability in the Mobile API that allows unauthenticated attackers to impersonate arbitrary users by supplying a crafted JSON payload in the 'g' HTTP header. The middleware in middleware.ts skips identity header generation when an Auth-Key header is…
When was CVE-2026-8890 disclosed?
CVE-2026-8890 was first published in the National Vulnerability Database on May 26, 2026, with the most recent update on July 23, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-8890 actively exploited?
CVE-2026-8890 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 39.3% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-8890?
CVE-2026-8890 has a CVSS v3 base score of 8.2 (NVD).
How do I remediate CVE-2026-8890?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-8890, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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