6.9
MEDIUM CVSS 4.0
CVE-2026-79661
Ech0 before 4.7.3 Unauthenticated fav_count Modification
Description

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.

INFO

Published Date :

Aug. 25, 2026, 12:16 p.m.

Last Modified :

Aug. 25, 2026, 12:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-79661 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Lin-snow ech0
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 MEDIUM [email protected]
CVSS 4.0 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 MEDIUM [email protected]
Solution
Implement authentication and rate limiting on the PUT /api/echo/like/:id endpoint.
  • Enforce authentication on the endpoint.
  • Implement rate limiting for requests.
  • Update to version 4.7.3 or later.
  • Review access controls for all endpoints.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-79661.

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

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-79661 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-79661 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-79661 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Aug. 25, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'lin-snow', 'product': 'Ech0', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '4.7.3', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '4.7.3', 'versionType': 'semver'}], 'packageURL': 'pkg:golang/github.com/lin-snow/Ech0', 'defaultStatus': 'unaffected'}]
    Added Description 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.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
    Added CWE CWE-770
    Added Reference https://github.com/lin-snow/Ech0/security/advisories/GHSA-pj6q-4vq4-r8cg
    Added Reference https://www.vulncheck.com/advisories/ech0-before-unauthenticated-fav-count-modification
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.