CVE-2026-79663 json
Ech0 before 4.7.3 Stored XSS via RSS feed tag names
published 2026-05-07 6 mo ago modified 2026-08-31 2 mo ago also GHSA-3v85-fqvh-7rxf , GO-2026-5100 , EUVD-2026-65451
- cvss
- 4.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 16%
- public exploits
- 0
- none known
Summary
Ech0 before 4.7.3 contains a stored cross-site scripting vulnerability in the public RSS feed where tag names and markdown content are rendered without HTML escaping. Attackers with admin privileges can inject malicious tag names or raw HTML in echo content that executes as JavaScript in RSS readers that render HTML-type summaries, affecting anonymous subscribers and other users.
Patch / fix
- go github.com/lin-snow/Ech0 1.4.8-0.20260503035519-fd320fe3e902
- go github.com/lin-snow/ech0 1.4.8-0.20260503035519-fd320fe3e902
- lin-snow Ech0 4.7.3
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2 mo ago
Exploit prediction
0.25% chance of exploitation in the next 30 days, higher than 16% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 4.8 | CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N |
| CNA | 3.1 | 4.8 | CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N |
| CNA | 4.0 | 4.8 | CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/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 |
| GitHub | 3.1 | 4.8 | CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| go | github.com/lin-snow/Ech0 | <1.4.8-0.20260503035519-fd320fe3e902 |
1.4.8-0.20260503035519-fd320fe3e902 |
| go | github.com/lin-snow/ech0 | <1.4.8-0.20260503035519-fd320fe3e902 |
1.4.8-0.20260503035519-fd320fe3e902 |
Affected products
- lin-snow Ech0
Classification
References
-
github.com
/lin-snow/Ech0/commit/fd320fe3e9021c8d8d284fb274775c018690520e
web
-
github.com
/lin-snow/Ech0/security/advisories/GHSA-3v85-fqvh-7rxf
vendor-advisory, web, advisory
-
vulncheck.com
/advisories/ech0-before-stored-xss-via-rss-feed-tag-names
third-party-advisory
-
github.com
/lin-snow/Ech0
package
Sources
- CVE List CVE-2026-79663
- GitHub Advisory GHSA-3v85-fqvh-7rxf
- NVD CVE-2026-79663
- OSV GO-2026-5100
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