CVE-2026-33129

MEDIUMNVD 5.95.9—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.9 under NVD CVSS v3. EPSS exploit probability: 0.3%, top 75% 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, nvd
5.9EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.9Exploit: None knownExposed: 0

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

H3 is a minimal H(TTP) framework. Versions 2.0.1-beta.0 through 2.0.0-rc.8 contain a Timing Side-Channel vulnerability in the requireBasicAuth function due to the use of unsafe string comparison (!==). This allows an attacker to deduce the valid password character-by-character by measuring the server's response time, effectively bypassing password complexity protections. This issue is fixed in version 2.0.1-rc.9.

CVSS v3
5.9
EG Score
5.9(medium)
EG Risk
31(Track)
EG Risk 31/100SSVC: 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
Severity59% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
25%
KEV
Not listed

Published

March 20, 2026

Last Modified

June 17, 2026

Advisory Details (3)

Auto-updated Aug 6, 2026
🔬 Proof of concept available. Patch available. Sources: github_pr, github_release, github.
github Patch Available🟡 PoC Available

observable timing discrepancy in basic auth utils · Advisory · h3js/h3 · GitHub

https://github.com/h3js/h3/security/advisories/GHSA-26f5-8h2x-34xh
github_release Patch Available

v2.0.1-rc.9

Patch available: h3js/h3 v2.0.1-rc.9

https://github.com/h3js/h3/releases/tag/v2.0.1-rc.9
github_pr Patch Available

fix(basic-auth): use jitter and constant-time string comparison

Patch available: h3js/h3 v2.0.1-rc.9 (PR #1283 merged 2026-01-17)

https://github.com/h3js/h3/pull/1283

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFixed inDependents
h3—2.0.1-rc.9—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 30× 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. 2026-09-18 19:28 UTCEPSS rescore
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-17 19:30 UTCEPSS rescore
  4. 2026-09-16 14:08 UTCEPSS rescore
  5. 2026-09-16 05:15 UTCEPSS rescore
  6. 2026-09-13 16:47 UTCEPSS rescore
  7. 2026-09-12 15:01 UTCEPSS rescore
  8. 2026-09-11 14:52 UTCEPSS rescore
  9. 2026-09-10 09:34 UTCEPSS rescore
  10. 2026-09-08 22:00 UTCEPSS rescore
  11. 2026-09-07 16:01 UTCEPSS rescore
  12. 2026-09-06 13:47 UTCEPSS rescore
  13. 2026-09-06 13:47 UTCEPSS rescore
  14. 2026-09-04 05:06 UTCEPSS rescore
  15. 2026-09-02 17:08 UTCOSV refresh
  16. 2026-09-02 14:11 UTCEPSS rescore
  17. 2026-09-01 13:53 UTCEPSS rescore
  18. 2026-09-01 04:39 UTCEPSS rescore
  19. 2026-09-01 04:39 UTCEPSS rescore
  20. 2026-08-30 19:17 UTCEPSS rescore
  21. 2026-08-30 01:22 UTCEPSS rescore
  22. 2026-08-28 21:41 UTCEPSS rescore
  23. 2026-08-27 14:25 UTCEPSS rescore
  24. 2026-08-26 14:46 UTCEPSS rescore
  25. 2026-08-25 13:49 UTCEPSS rescore
Show 34 more
  1. 2026-08-24 14:17 UTCEPSS rescore
  2. 2026-08-23 00:19 UTCEPSS rescore
  3. 2026-08-21 23:49 UTCEPSS rescore
  4. 2026-08-20 22:55 UTCEPSS rescore
  5. 2026-08-20 22:55 UTCEPSS rescore
  6. 2026-08-19 17:03 UTCEPSS rescore
  7. 2026-08-18 13:48 UTCEPSS rescore
  8. 2026-08-17 13:47 UTCEPSS rescore
  9. 2026-08-16 14:56 UTCEPSS rescore
  10. 2026-08-16 11:02 UTCEG score recompute
  11. 2026-08-16 02:14 UTCEPSS rescore
  12. 2026-08-15 01:30 UTCEPSS rescore
  13. 2026-08-14 07:13 UTCEG score recompute
  14. 2026-08-13 22:00 UTCEPSS rescore
  15. 2026-08-12 21:53 UTCEG score recompute
  16. 2026-08-12 13:50 UTCEPSS rescore
  17. 2026-08-11 04:25 UTCEG score recompute
  18. 2026-08-11 00:00 UTCEPSS rescore
  19. 2026-08-10 05:36 UTCEG score recompute
  20. 2026-08-09 13:46 UTCEPSS rescore
  21. 2026-08-09 06:46 UTCEG score recompute
  22. 2026-08-08 16:37 UTCEPSS rescore
  23. 2026-08-07 17:15 UTCEG score recompute
  24. 2026-08-06 13:46 UTCEPSS rescore
  25. 2026-08-06 01:28 UTCEG score recompute
  26. 2026-08-05 19:17 UTCEPSS rescore
  27. 2026-08-04 15:10 UTCEPSS rescore
  28. 2026-08-04 10:38 UTCEPSS rescore
  29. 2026-08-02 16:13 UTCEG score recompute
  30. 2026-08-01 04:16 UTCEPSS rescore
  31. 2026-07-30 16:28 UTCEPSS rescore
  32. 2026-07-30 01:30 UTCEPSS rescore
  33. 2026-07-27 14:35 UTCEG score recompute
  34. 2026-07-27 14:27 UTCOSV refresh

Frequently asked(5)

What is CVE-2026-33129?
CVE-2026-33129 is a medium vulnerability published on March 20, 2026. H3 is a minimal H(TTP) framework. Versions 2.0.1-beta.0 through 2.0.0-rc.8 contain a Timing Side-Channel vulnerability in the requireBasicAuth function due to the use of unsafe string comparison (!==). This allows an attacker to deduce the valid password character-by-character by measuring the…
When was CVE-2026-33129 disclosed?
CVE-2026-33129 was first published in the National Vulnerability Database on March 20, 2026, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-33129 actively exploited?
CVE-2026-33129 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 74.9% of all scored CVEs.
What is the CVSS score of CVE-2026-33129?
CVE-2026-33129 has a CVSS v3 base score of 5.9 (NVD).
How do I remediate CVE-2026-33129?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-33129, 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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