CVE-2026-3833

HIGHNVD 7.46.5▼
EchelonGraph scoreMEDIUM confidence

Score 6.5 from GitHub Security Advisory published 2026-04-30. NVD baseline CVSS 7.4; sources differ by 0.9.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Elevated
7.4
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 1%CVSS: 7.4Exploit: NoneExposed: 0

A fix is available — apply it.

A flaw was found in gnutls. This vulnerability occurs because gnutls performs case-sensitive comparisons of nameConstraints labels, specifically for dNSName (DNS) or rfc822Name (email) constraints within excludedSubtrees or permittedSubtrees. A remote attacker can exploit this by crafting a leaf certificate with casing differences in the Subject Alternative Name (SAN), leading to a policy bypass where a certificate that should be rejected is instead accepted. This could result in unauthorized access or information disclosure.

CVSS v3
7.4
EG Score
6.5(medium)
EPSS
43.0%
KEV
Not listed

Published

April 30, 2026

Last Modified

June 30, 2026

Advisory Details (3)

Auto-updated Apr 30, 2026
🔬 Proof of concept available. Patch available. Sources: redhat.
generic🟡 PoC Available

[Moderate] gnutls x509 nameconstraints: excluded dns/email subtree bypass via case-sensitive comparison (security report) (#1803) · Issues · gnutls / GnuTLS · GitLab

https://gitlab.com/gnutls/gnutls/-/issues/1803
redhat

2445763 – (CVE-2026-3833) CVE-2026-3833 gnutls: GnuTLS: Policy bypass due to case-sensitive nameConstraints comparison

https://bugzilla.redhat.com/show_bug.cgi?id=2445763
redhat Patch Available

cve-details

https://access.redhat.com/security/cve/CVE-2026-3833

Vendor Advisories for CVE-2026-3833(14)

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

Patch Availability(5)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulibgnutls30t64 (3.8.12-2ubuntu1.1) @ resolute2026-06-14ubuntu
redhatgnutls-0:3.8.10-4.el9_82026-05-26redhat
redhatgnutls-0:3.8.10-4.el10_22026-05-26redhat
redhatgnutls-0:3.6.16-8.el8_10.62026-05-26redhat
redhatgnutls-main-3.8.13-1.hum12026-05-02redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(1)

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

Additional Vendor Advisories

(1)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 9× in last 7d / 46× 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.

Showing the most recent 100 of 121 total refreshes for this CVE.

  1. 2026-07-11 08:27 UTCEPSS rescore
  2. 2026-07-09 19:10 UTCEPSS rescore
  3. 2026-07-08 15:15 UTCEPSS rescore
  4. 2026-07-07 13:46 UTCEPSS rescore
  5. 2026-07-06 16:27 UTCEPSS rescore
  6. 2026-07-06 16:27 UTCEPSS rescore
  7. 2026-07-06 02:23 UTCEPSS rescore
  8. 2026-07-06 02:23 UTCEPSS rescore
  9. 2026-07-05 02:30 UTCEPSS rescore
  10. 2026-07-04 06:31 UTCEPSS rescore
  11. 2026-07-01 15:06 UTCEPSS rescore
  12. 2026-06-30 23:22 UTCEPSS rescore
  13. 2026-06-29 14:06 UTCEPSS rescore
  14. 2026-06-29 13:24 UTCNVD updateCVSS v3 → 7.4 · severity → HIGH
  15. 2026-06-29 12:02 UTCMITRE cvelistV5CVSS v3 → 6.5 · severity → MEDIUM
  16. 2026-06-29 10:04 UTCNVD updateCVSS v3 → 7.4 · severity → HIGH
  17. 2026-06-29 08:47 UTCMITRE cvelistV5CVSS v3 → 6.5 · severity → MEDIUM
  18. 2026-06-28 14:07 UTCEPSS rescore
  19. 2026-06-28 04:56 UTCEPSS rescore
  20. 2026-06-27 03:08 UTCEPSS rescore
  21. 2026-06-25 13:49 UTCEPSS rescore
  22. 2026-06-25 13:49 UTCEPSS rescore
  23. 2026-06-24 14:05 UTCEPSS rescore
  24. 2026-06-24 11:53 UTCNVD updateCVSS v3 → 7.4 · severity → HIGH
  25. 2026-06-23 21:33 UTCEPSS rescore
Show 75 more
  1. 2026-06-22 14:25 UTCEPSS rescore
  2. 2026-06-22 14:25 UTCEPSS rescore
  3. 2026-06-21 22:58 UTCMITRE cvelistV5CVSS v3 → 6.5 · severity → MEDIUM
  4. 2026-06-21 14:56 UTCEPSS rescore
  5. 2026-06-21 14:56 UTCEPSS rescore
  6. 2026-06-21 01:59 UTCEPSS rescore
  7. 2026-06-19 19:25 UTCEPSS rescore
  8. 2026-06-18 17:52 UTCEPSS rescore
  9. 2026-06-18 17:52 UTCEPSS rescore
  10. 2026-06-17 17:53 UTCEPSS rescore
  11. 2026-06-16 17:52 UTCEPSS rescore
  12. 2026-06-15 17:49 UTCEPSS rescore
  13. 2026-06-14 09:16 UTCEG score recompute
  14. 2026-06-14 09:16 UTCVendor advisory
  15. 2026-06-14 09:16 UTCGHSA enrichment
  16. 2026-06-13 23:00 UTCEPSS rescore
  17. 2026-06-12 23:12 UTCEPSS rescore
  18. 2026-06-12 23:12 UTCEPSS rescore
  19. 2026-06-12 05:33 UTCEG score recompute
  20. 2026-06-12 05:33 UTCVendor advisory
  21. 2026-06-12 05:33 UTCGHSA enrichment
  22. 2026-06-11 14:00 UTCEPSS rescore
  23. 2026-06-11 04:48 UTCEG score recompute
  24. 2026-06-11 04:48 UTCVendor advisory
  25. 2026-06-11 04:48 UTCGHSA enrichment
  26. 2026-06-10 22:18 UTCEPSS rescore
  27. 2026-06-10 13:22 UTCEPSS rescore
  28. 2026-06-10 13:22 UTCEPSS rescore
  29. 2026-06-10 00:25 UTCEG score recompute
  30. 2026-06-10 00:25 UTCVendor advisory
  31. 2026-06-10 00:25 UTCGHSA enrichment
  32. 2026-06-08 23:40 UTCEG score recompute
  33. 2026-06-08 23:40 UTCVendor advisory
  34. 2026-06-08 23:40 UTCGHSA enrichment
  35. 2026-06-08 23:31 UTCNVD updateCVSS v3 → 7.4 · severity → HIGH
  36. 2026-06-08 14:17 UTCEPSS rescore
  37. 2026-06-08 14:17 UTCEPSS rescore
  38. 2026-06-07 15:45 UTCEG score recompute
  39. 2026-06-07 15:45 UTCVendor advisory
  40. 2026-06-07 15:45 UTCGHSA enrichment
  41. 2026-06-07 15:25 UTCEPSS rescore
  42. 2026-06-07 15:25 UTCEPSS rescore
  43. 2026-06-07 15:25 UTCEPSS rescore
  44. 2026-06-06 15:00 UTCEG score recompute
  45. 2026-06-06 15:00 UTCVendor advisory
  46. 2026-06-06 15:00 UTCGHSA enrichment
  47. 2026-06-06 13:47 UTCEPSS rescore
  48. 2026-06-06 13:47 UTCEPSS rescore
  49. 2026-06-05 22:47 UTCEPSS rescore
  50. 2026-06-05 22:47 UTCEPSS rescore
  51. 2026-06-05 13:39 UTCEG score recompute
  52. 2026-06-05 13:39 UTCVendor advisory
  53. 2026-06-05 13:39 UTCGHSA enrichment
  54. 2026-06-05 06:10 UTCEPSS rescore
  55. 2026-06-05 06:10 UTCEPSS rescore
  56. 2026-06-04 13:12 UTCEPSS rescore
  57. 2026-06-04 13:12 UTCEPSS rescore
  58. 2026-06-04 12:52 UTCEG score recompute
  59. 2026-06-04 12:52 UTCVendor advisory
  60. 2026-06-04 12:52 UTCGHSA enrichment
  61. 2026-06-03 12:07 UTCEG score recompute
  62. 2026-06-03 12:07 UTCVendor advisory
  63. 2026-06-03 12:07 UTCGHSA enrichment
  64. 2026-06-02 20:13 UTCEPSS rescore
  65. 2026-06-02 11:22 UTCEG score recompute
  66. 2026-06-02 11:22 UTCVendor advisory
  67. 2026-06-02 11:22 UTCGHSA enrichment
  68. 2026-06-01 13:52 UTCEPSS rescore
  69. 2026-06-01 13:52 UTCEPSS rescore
  70. 2026-06-01 13:51 UTCEPSS rescore
  71. 2026-06-01 10:37 UTCEG score recompute
  72. 2026-06-01 10:37 UTCVendor advisory
  73. 2026-06-01 10:37 UTCGHSA enrichment
  74. 2026-05-31 22:30 UTCEPSS rescore
  75. 2026-05-31 22:30 UTCEPSS rescore

Frequently asked(5)

What is CVE-2026-3833?
CVE-2026-3833 is a high vulnerability published on April 30, 2026. A flaw was found in gnutls. This vulnerability occurs because gnutls performs case-sensitive comparisons of nameConstraints labels, specifically for dNSName (DNS) or rfc822Name (email) constraints within excludedSubtrees or permittedSubtrees. A remote attacker can exploit this by crafting a leaf…
When was CVE-2026-3833 disclosed?
CVE-2026-3833 was first published in the National Vulnerability Database on April 30, 2026, with the most recent update on June 30, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-3833 actively exploited?
CVE-2026-3833 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 43.0% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-3833?
CVE-2026-3833 has a CVSS v3 base score of 7.4 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 6.5.
How do I remediate CVE-2026-3833?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-3833, 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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