CVE-2026-88861

HIGHPre-NVD 8.38.3—
EchelonGraph scoreHIGH confidence

Score 8.3 from GitHub Security Advisory (severity: HIGH) published 2026-09-10. a secondary CVSS source baseline 8.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this weekElevated
8.3EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 8.3Exploit: Elevated riskExposed: 0

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

Capgo (Cap-go/capgo.app) contains an authentication bypass affecting all versions (no patched version available at time of publication). The Edge authorization path allows a password-only Supabase aal1 session to exercise privileged RBAC permissions even when the account has a verified MFA factor that has not been used for the session: the Edge JWT middleware (foundJWT() in supabase/functions/_backend/utils/hono_middleware.ts) accepts the JWT without validating its assurance level, and the direct RBAC path (checkPermission()/checkPermissionPg() in supabase/functions/_backend/utils/rbac.ts calling public.rbac_check_permission_direct()) authorizes by user ID without passing or checking the session aal, unlike the public.verify_mfa() control which correctly requires aal2. An attacker who knows only the victim's password can therefore authenticate, mint a persistent app-scoped app_admin API key that remains valid after the aal1 session is logged out, and perform privileged operations such as modifying production OTA channel configurations (validated by changing a public production channel from bundle 1.0.0 to 1.0.1), defeating the protection provided by MFA.

CVSS v3
8.3
EG Score
8.3(high)
EG Risk
53(Track*)
EG Risk 53/100SSVC: 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 computed
Severity83% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Watch closely — could escalate to Attend.
EPSS PROB
0%
EPSS %ILE
22%
KEV
Not listed

Published

September 10, 2026

Last Modified

September 15, 2026

Advisory Details (2)

Auto-updated Sep 10, 2026
🔬 Proof of concept available. Patch available. Sources: github.
generic

Capgo AAL1 Session MFA Bypass via Direct RBAC Authorization | Advisories | VulnCheck

https://www.vulncheck.com/advisories/capgo-aal1-session-mfa-bypass-via-direct-rbac-authorization
github Patch Available🟡 PoC Available

Password-only AAL1 sessions bypass enrolled MFA and can mint persistent app_admin API keys · Advisory · Cap-go/capgo.app · GitHub

https://github.com/Cap-go/capgo.app/security/advisories/GHSA-9435-5xw9-v29h

Vendor Advisories for CVE-2026-88861(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 30× in last 7d / 42× 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.

  1. 2026-09-19 13:25 UTCGHSA enrichment
  2. 2026-09-19 01:42 UTCEG score recompute
  3. 2026-09-19 01:42 UTCGHSA enrichment
  4. 2026-09-18 19:28 UTCEPSS rescore
  5. 2026-09-18 13:58 UTCGHSA enrichment
  6. 2026-09-18 02:15 UTCEG score recompute
  7. 2026-09-18 02:15 UTCGHSA enrichment
  8. 2026-09-17 19:32 UTCEPSS rescore
  9. 2026-09-17 14:32 UTCGHSA enrichment
  10. 2026-09-17 02:48 UTCGHSA enrichment
  11. 2026-09-16 15:03 UTCEG score recompute
  12. 2026-09-16 15:02 UTCGHSA enrichment
  13. 2026-09-16 14:09 UTCEPSS rescore
  14. 2026-09-16 05:15 UTCEPSS rescore
  15. 2026-09-16 03:19 UTCGHSA enrichment
  16. 2026-09-15 15:34 UTCEG score recompute
  17. 2026-09-15 15:34 UTCGHSA enrichment
  18. 2026-09-15 14:18 UTCEG score recompute
  19. 2026-09-15 14:18 UTCGHSA enrichment
  20. 2026-09-15 12:32 UTCEG score recompute
  21. 2026-09-15 12:32 UTCGHSA enrichment
  22. 2026-09-15 03:12 UTCEPSS rescore
  23. 2026-09-15 00:48 UTCGHSA enrichment
  24. 2026-09-14 13:05 UTCGHSA enrichment
  25. 2026-09-14 01:22 UTCEG score recompute
Show 17 more
  1. 2026-09-14 01:22 UTCGHSA enrichment
  2. 2026-09-13 16:48 UTCEPSS rescore
  3. 2026-09-13 13:39 UTCGHSA enrichment
  4. 2026-09-13 01:56 UTCEG score recompute
  5. 2026-09-13 01:56 UTCGHSA enrichment
  6. 2026-09-12 15:02 UTCEPSS rescore
  7. 2026-09-12 14:12 UTCGHSA enrichment
  8. 2026-09-12 02:28 UTCEG score recompute
  9. 2026-09-12 02:28 UTCGHSA enrichment
  10. 2026-09-11 14:53 UTCEPSS rescore
  11. 2026-09-11 14:53 UTCEPSS rescore
  12. 2026-09-11 14:45 UTCGHSA enrichment
  13. 2026-09-11 03:01 UTCEG score recompute
  14. 2026-09-11 03:01 UTCGHSA enrichment
  15. 2026-09-10 14:20 UTCEG score recompute
  16. 2026-09-10 13:20 UTCEG score recompute
  17. 2026-09-10 13:20 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-88861?
CVE-2026-88861 is a high vulnerability published on September 10, 2026. Capgo (Cap-go/capgo.app) contains an authentication bypass affecting all versions (no patched version available at time of publication). The Edge authorization path allows a password-only Supabase aal1 session to exercise privileged RBAC permissions even when the account has a verified MFA factor…
When was CVE-2026-88861 disclosed?
CVE-2026-88861 was first published in the National Vulnerability Database on September 10, 2026, with the most recent update on September 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-88861 actively exploited?
CVE-2026-88861 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 78.1% of all scored CVEs.
What is the CVSS score of CVE-2026-88861?
CVE-2026-88861 has a CVSS v3 base score of 8.3 (NVD).
How do I remediate CVE-2026-88861?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-88861, 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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