CVE-2026-13676

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 81% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
7.5
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 7.5Exploit: NoneExposed: 0

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

fast-uri versions 2.3.1 through 3.1.2 and 4.0.0 fail to canonicalize Unicode (IDN) hostnames for HTTP-family URLs. The IDN conversion path calls a helper that does not exist on the global URL constructor, silently leaving the host in its original Unicode form while normalize() and equal() still return values that differ from a WHATWG-compatible URL parser. Applications that use fast-uri to enforce host-based policy (denylists, loopback filtering, redirect validation, outbound proxy routing) before passing the same URL to Node's URL or fetch can be bypassed when the two implementations resolve the same input to different hosts. Patches: upgrade to fast-uri 3.1.3 for the 3.x line or 4.0.1 for the 4.x line. Workarounds: enforce host policy using the same URL parser used for the actual request, or reject non-ASCII hosts before policy checks.

CVSS v3
7.5
EG Score
7.5(medium)
EPSS
19.2%
KEV
Not listed

Published

June 29, 2026

Last Modified

July 10, 2026

Advisory Details (2)

Auto-updated Jun 29, 2026
Patch available. Sources: github.
github Patch Available

fast-uri vulnerable to host confusion via failed IDN canonicalization · Advisory · fastify/fast-uri · GitHub

https://github.com/fastify/fast-uri/security/advisories/GHSA-4c8g-83qw-93j6
generic

Security Advisories | OpenJS Foundation CVE Numbering Authority

https://cna.openjsf.org/security-advisories.html

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 24× in last 7d / 41× 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. 2026-07-11 12:29 UTCEG score recompute
  2. 2026-07-11 08:27 UTCEPSS rescore
  3. 2026-07-11 01:29 UTCEG score recompute
  4. 2026-07-10 14:27 UTCEG score recompute
  5. 2026-07-10 03:21 UTCEG score recompute
  6. 2026-07-09 19:10 UTCEPSS rescore
  7. 2026-07-09 16:20 UTCEG score recompute
  8. 2026-07-09 05:17 UTCEG score recompute
  9. 2026-07-08 18:17 UTCEG score recompute
  10. 2026-07-08 15:15 UTCEPSS rescore
  11. 2026-07-08 15:15 UTCEPSS rescore
  12. 2026-07-08 07:16 UTCEG score recompute
  13. 2026-07-07 20:05 UTCEG score recompute
  14. 2026-07-07 13:46 UTCEPSS rescore
  15. 2026-07-07 09:03 UTCEG score recompute
  16. 2026-07-06 22:02 UTCEG score recompute
  17. 2026-07-06 16:27 UTCEPSS rescore
  18. 2026-07-06 11:00 UTCEG score recompute
  19. 2026-07-06 02:23 UTCEPSS rescore
  20. 2026-07-05 23:56 UTCEG score recompute
  21. 2026-07-05 12:56 UTCEG score recompute
  22. 2026-07-05 02:30 UTCEPSS rescore
  23. 2026-07-05 02:30 UTCEPSS rescore
  24. 2026-07-05 01:54 UTCEG score recompute
  25. 2026-07-04 14:54 UTCEG score recompute
Show 16 more
  1. 2026-07-04 06:31 UTCEPSS rescore
  2. 2026-07-04 03:53 UTCEG score recompute
  3. 2026-07-03 16:43 UTCEG score recompute
  4. 2026-07-03 05:42 UTCEG score recompute
  5. 2026-07-02 18:41 UTCEG score recompute
  6. 2026-07-02 07:40 UTCEG score recompute
  7. 2026-07-01 20:38 UTCEG score recompute
  8. 2026-07-01 15:06 UTCEPSS rescore
  9. 2026-07-01 15:06 UTCEPSS rescore
  10. 2026-07-01 09:38 UTCEG score recompute
  11. 2026-06-30 23:22 UTCEPSS rescore
  12. 2026-06-30 22:37 UTCEG score recompute
  13. 2026-06-30 11:36 UTCEG score recompute
  14. 2026-06-30 00:33 UTCEG score recompute
  15. 2026-06-29 13:33 UTCEG score recompute
  16. 2026-06-29 13:32 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-13676?
CVE-2026-13676 is a high vulnerability published on June 29, 2026. fast-uri versions 2.3.1 through 3.1.2 and 4.0.0 fail to canonicalize Unicode (IDN) hostnames for HTTP-family URLs. The IDN conversion path calls a helper that does not exist on the global URL constructor, silently leaving the host in its original Unicode form while normalize() and equal() still…
When was CVE-2026-13676 disclosed?
CVE-2026-13676 was first published in the National Vulnerability Database on June 29, 2026, with the most recent update on July 10, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-13676 actively exploited?
CVE-2026-13676 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 19.2% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-13676?
CVE-2026-13676 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-13676?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-13676, 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

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