CVE-2026-79663

MEDIUMPre-NVD 4.84.8—
EchelonGraph scoreHIGH confidence

Score 4.8 from GitHub Security Advisory published 2026-08-25. a secondary CVSS source baseline 4.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
4.8EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 4.8Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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.

CVSS v3
4.8
EG Score
4.8(high)
EG Risk
22(Track)
EG Risk 22/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity48% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
4%
KEV
Not listed

Published

August 25, 2026

Last Modified

August 26, 2026

Advisory Details (2)

Auto-updated Aug 25, 2026
🔬 Proof of concept available. Patch available. Sources: github.
generic

Ech0 before 4.7.3 Stored XSS via RSS feed tag names | Advisories | VulnCheck

https://www.vulncheck.com/advisories/ech0-before-stored-xss-via-rss-feed-tag-names
github Patch Available🟡 PoC Available

RSS feed renders unescaped tag names and raw-HTML markdown, stored XSS against subscribers · Advisory · lin-snow/Ech0 · GitHub

https://github.com/lin-snow/Ech0/security/advisories/GHSA-3v85-fqvh-7rxf

Vendor Advisories for CVE-2026-79663(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(2 across 1 ecosystem)
Go(2)
PackageVulnerable rangeFixed inDependents
github.com/lin-snow/ech0—1.4.8-0.20260503035519-fd320fe3e902—
github.com/lin-snow/Ech0—1.4.8-0.20260503035519-fd320fe3e902—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 19× in last 7d / 19× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-30 01:30 UTCEG score recompute
  2. 2026-08-30 01:30 UTCGHSA enrichment
  3. 2026-08-30 01:22 UTCEPSS rescore
  4. 2026-08-29 00:17 UTCEG score recompute
  5. 2026-08-29 00:17 UTCGHSA enrichment
  6. 2026-08-28 21:42 UTCEPSS rescore
  7. 2026-08-27 18:42 UTCEG score recompute
  8. 2026-08-27 18:41 UTCGHSA enrichment
  9. 2026-08-27 14:25 UTCEPSS rescore
  10. 2026-08-26 17:23 UTCEG score recompute
  11. 2026-08-26 17:23 UTCGHSA enrichment
  12. 2026-08-26 16:23 UTCEG score recompute
  13. 2026-08-26 16:23 UTCGHSA enrichment
  14. 2026-08-26 14:47 UTCEPSS rescore
  15. 2026-08-26 13:30 UTCEG score recompute
  16. 2026-08-26 13:30 UTCGHSA enrichment
  17. 2026-08-25 12:17 UTCEG score recompute
  18. 2026-08-25 11:42 UTCEG score recompute
  19. 2026-08-25 11:41 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-79663?
CVE-2026-79663 is a medium vulnerability published on August 25, 2026. 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…
When was CVE-2026-79663 disclosed?
CVE-2026-79663 was first published in the National Vulnerability Database on August 25, 2026, with the most recent update on August 26, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-79663 actively exploited?
CVE-2026-79663 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 95.7% of all scored CVEs.
What is the CVSS score of CVE-2026-79663?
CVE-2026-79663 has a CVSS v3 base score of 4.8 (NVD).
How do I remediate CVE-2026-79663?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-79663, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-79663

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