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TI-2026-55168 Aliases CVE-2026-79670GHSA-mj42-9vh2-f8v3

Ech0 before 4.4.3 Stored XSS via SVG Upload

Priority MEDIUM 55CWE-434Published · Updated

Key facts

Attack vector
Network
Privileges required
High
User interaction
Passive
Attack complexity
Low
Attack requirements
None
Impact type
Code execution
Confidentiality · integrity · availability
Low · Low · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-434.

Summary

Ech0 before 4.4.3 contains a stored cross-site scripting vulnerability in the file upload endpoint that validates Content-Type using only client-supplied headers without server-side inspection. Attackers with admin privileges can upload SVG or HTML files containing JavaScript that executes in the application origin when accessed by any user, enabling session hijacking and data exfiltration.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00251 16th percentileScored 2026-11-07
Fix Fixed Ech0 (lin-snow): 4.4.3

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

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 4.4.34.4.3Patch availableCNA
  • Ech0 Vendorlin-snow Affected before 4.4.3 Fixed in 4.4.3 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 4.4.3

Fixed in the same release

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

  • Release ·

    lin-snow Ech0 4.4.3

    7 records Highest priority Priority HIGH 1 HIGH, 5 MEDIUM, 1 LOW

    Other records, highest priority first

    • TI-2026-55165 Ech0 before 4.4.3 Authentication Bypass via Scope EnforcementPriority HIGH 65
    • TI-2026-55170 Ech0 before 4.4.3 Authentication Bypass via Comment PanelPriority MEDIUM 64
    • TI-2026-55164 Ech0 before 4.4.3 Missing Authorization via dashboard log endpointsPriority MEDIUM 64

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-79670
  2. 2026-10-03 Alias added: GHSA-mj42-9vh2-f8v3

References

  • TI-2026-55162 Ech0 before 4.7.3 Access Token Revocation Bypass CVSS 4.0CRITICAL 9.1
  • 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
See all 19 →

Sources