Auth bypass in Lin-Snow Ech0
CVE-2026-79668
Ech0 before 4.7.3 contains an authentication bypass vulnerability in the PUT /api/echo/like/:id endpoint that allows unauthenticated attackers to increment engagement metrics without identity verification or rate limiting. Attackers can send repeated requests to arbitrarily inflate the fav_count field for any known echo identifier, compromising the integrity of engagement metrics and social ranking systems.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.004 (35.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 36th percentile — 35.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.002
Affected products
Weakness classification (CWE)
References
- github.com/lin-snow/Ech0/security/advisories/GHSA-rgj7-vg8v-j4wr (vendor-advisory)
- www.vulncheck.com/advisories/ech0-before-unauthenticated-like-endpoint-metric-i… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-79668?
- CVE-2026-79668 is a medium-severity vulnerability in Lin-Snow Ech0, classified under Missing Authentication for Critical Function. CVSS score: 5.3/10. Published 2026-08-25.
- How severe is CVE-2026-79668?
- Medium severity. CVSS v3 base score is 5.3 out of 10.