CVE-2026-79660: Ech0 email disclosure via public API endpoints

CVE-2026-79660 · Severity: medium · CVSS 5.3 · Published 2026-08-25

Ech0 is a commenting platform that allows guest users to submit comments and provide email addresses for moderation and reply notifications. Due to improper data exposure settings, unauthenticated attackers can harvest all guest commenter email addresses by making simple API requests to public endpoints. This exposes users' private email addresses without their knowledge or consent, creating privacy compliance risks and enabling targeted phishing campaigns.

Technologies: github.com/lin-snow/ech0 (Go), Lin-Snow Ech0. Vendors: Go, Lin-Snow.

Quick answers

Is CVE-2026-79660 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-79660 being exploited in the wild.
How severe is CVE-2026-79660?
Medium severity, with a CVSS score of 5.3, published 25 August 2026.
Which products and versions are affected?
github.com/lin-snow/ech0 (Go) SEMVER:introduced=0,fixed=1.4.8-0.20260503034700-cb8d7a997dd8; Lin-Snow Ech0 before 4.7.3.
Is there a fix for CVE-2026-79660?
Yes. github.com/lin-snow/ech0 (Go): upgrade to 1.4.8-0.20260503034700-cb8d7a997dd8 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-79660 attacked?
It is attacked over the network, in a web application.
Am I affected by CVE-2026-79660?
Check whether you run github.com/lin-snow/ech0 (Go) or Lin-Snow Ech0 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • github.com/lin-snow/ech0 (Go): upgrade to 1.4.8-0.20260503034700-cb8d7a997dd8 or later
    go get github.com/lin-snow/ech0@v1.4.8-0.20260503034700-cb8d7a997dd8

Technical details

The vulnerability is an information exposure issue (CWE-200) caused by improper JSON serialization configuration on the Comment model. The Email field in internal/model/comment/comment.go uses json:"email" instead of json:"-" (which is correctly applied to other PII fields like IPHash and UserAgent), causing the field to be included in JSON responses. The public endpoints GET /api/comments?echo_id=X and GET /api/comments/public?limit=N on PublicRouterGroup require no authentication and return raw Comment structs without field projection or stripping. An unauthenticated attacker can iterate through these endpoints to harvest every guest commenter's email address on an instance. The fix is to change the JSON tag to json:"-" or introduce a PublicComment DTO that excludes the email field. Versions before 4.7.3 are affected; patched version 4.7.3 is available.

Affected products

  • lin-snow Ech0 before 4.7.3

Identifiers

  • CVE-2026-79660
  • GHSA-rj4g-rqgh-rx9h
  • GO-2026-5626

Timeline

  • 2026-05-03: disclosed: GitHub Security Advisory GHSA-rj4g-rqgh-rx9h published
  • 2026-08-25: advisory: CVE-2026-79660 published
  • 2026-04-03: patched: Patched in version 4.7.3

References

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