CVE-2026-79661

Ech0 through 4.5.6 registers the PUT /api/echo/like/:id endpoint on the public router group without authentication or rate limiting. Unauthenticated attackers can increment the fav_count counter of any echo (including private echoes) by supplying its UUID, which can be harvested from the public GET /api/echo/page feed. Repeated requests are accepted without deduplication, each triggering a database write and a four-key cache invalidation, allowing attackers to inflate popularity metrics and amplify load on the database and cache. Fixed in 4.7.3.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/lin-snow/Ech0/security/advisories/GHSA-pj6q-4vq4-r8cg
https://www.vulncheck.com/advisories/ech0-before-unauthenticated-fav-count-modification
https://github.com/lin-snow/Ech0/security/advisories/GHSA-pj6q-4vq4-r8cg

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-25 12:16

Updated : 2026-08-31 20:50

NVD link : CVE-2026-79661

Mitre link : CVE-2026-79661

CVE.ORG link : CVE-2026-79661

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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