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TI-2026-55162 Aliases CVE-2026-79664GHSA-3r5q-vfpj-wprr

Ech0 before 4.7.3 Access Token Revocation Bypass

Priority HIGH 74CWE-613Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Attack requirements
Present
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-613.

Summary

Ech0 before 4.7.3 fails to properly revoke access tokens created with never-expire option, allowing attackers to maintain perpetual authenticated access after token theft. Three independent revocation mechanisms fail: logout panics on nil ExpiresAt field, RevokeToken skips when remainTTL is zero, and admin delete does not blacklist the JTI, leaving stolen tokens cryptographically valid until JWT secret rotation.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00356 29th percentileScored 2026-11-07
Fix Fixed Ech0 (lin-snow): 4.7.3

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
lin-snowEch0before 4.7.34.7.3Patch availableCNA
  • Ech0 Vendorlin-snow Affected before 4.7.3 Fixed in 4.7.3 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:ech0:ech0:*:*:*:*:*:*:*:*——lin-snow
  • cpe:2.3:a:ech0:ech0:*:*:*:*:*:*:*:* Versions — — ·lin-snow

Remediation

  • Fix · CNA Ech0 (lin-snow) Fixed in 4.7.3

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    lin-snow Ech0 4.7.3

    7 records Highest priority Priority HIGH 5 HIGH, 2 LOW

    Other records, highest priority first

    • TI-2026-55160 Ech0 before 4.7.3 OAuth Redirect URI Validation BypassPriority HIGH 73
    • TI-2026-55159 Ech0 before 4.7.3 Unauthenticated fav_count ModificationPriority HIGH 70
    • TI-2026-55158 Ech0 before 4.7.3 Email Disclosure via Public APIPriority HIGH 70
    Show all 7 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-79664
  2. 2026-10-03 Alias added: GHSA-3r5q-vfpj-wprr

References

Advisory 1

  • TI-2026-55163 Ech0 before 4.5.1 Authorization Bypass via Session Tokens CVSS 4.0HIGH 8.7
  • TI-2026-55160 Ech0 before 4.7.3 OAuth Redirect URI Validation Bypass CVSS 4.0HIGH 8.8
  • TI-2026-27239 Ech0 Affected by Unauthenticated Server-Side Request Forgery in Website Preview Feature CVSS 3.1HIGH 7.5
  • TI-2026-27240 Ech0 affected by unauthenticated SSRF in GetWebsiteTitle allows access to internal services and cloud metadata CVSS 3.1HIGH 7.2
  • TI-2026-55159 Ech0 before 4.7.3 Unauthenticated fav_count Modification CVSS 4.0MEDIUM 6.9
  • TI-2026-55158 Ech0 before 4.7.3 Email Disclosure via Public API CVSS 4.0MEDIUM 6.9
See all 19 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences