CVE-2026-44249

HIGHPre-NVD 8.18.1—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 8.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.6%, top 58% 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
Trending — Patch released this week
8.1
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 1%CVSS: 8.1Exploit: NoneExposed: 0

A fix is available — apply it.

Netty is a network application framework for development of protocol servers and clients. In netty-handler prior to versions 4.1.135.Final and 4.2.15.Final, an attacker can bypass IPv6 subnet rules due to an incorrect masking operation in IpSubnetFilterRule.compareTo(). Valid public IP addresses can bypass the restrictions. Versions 4.1.135.Final and 4.2.15.Final patch the issue.

CVSS v3
8.1
EG Score
8.1(medium)
EPSS
42.1%
KEV
Not listed

Published

June 8, 2026

Last Modified

July 3, 2026

Advisory Details (3)

Auto-updated Jun 12, 2026
Patch available. Sources: github_release, github.
github Patch Available

IPv6 Subnet Filter Bypass via Incorrect Comparator Masking · Advisory · netty/netty · GitHub

https://github.com/netty/netty/security/advisories/GHSA-3qp7-7mw8-wx86
github_release Patch Available

netty-4.2.15.Final

Patch available: netty/netty netty-4.2.15.Final

https://github.com/netty/netty/releases/tag/netty-4.2.15.Final
github_release Patch Available

netty-4.1.135.Final

Patch available: netty/netty netty-4.1.135.Final

https://github.com/netty/netty/releases/tag/netty-4.1.135.Final

Vendor Advisories for CVE-2026-44249(6)

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

Patch Availability(2)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatnetty-handler2026-07-02redhat
redhatoffline-knowledge-portal/rhokp-rhel9:17822393702026-06-23redhat

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.

Affected Packages

(1 across 1 ecosystem)
Maven(1)
PackageVulnerable rangeFixed inDependents
io.netty:netty-handler4.0.0.Alpha1 ... 4.1.99.Final (228 versions)4.1.135.Final—

Weakness Classification(3)

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

Data Freshness Timeline

(refreshed 26× in last 7d / 117× 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 117 total refreshes for this CVE.

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

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Frequently asked(5)

What is CVE-2026-44249?
CVE-2026-44249 is a high vulnerability published on June 8, 2026. Netty is a network application framework for development of protocol servers and clients. In netty-handler prior to versions 4.1.135.Final and 4.2.15.Final, an attacker can bypass IPv6 subnet rules due to an incorrect masking operation in IpSubnetFilterRule.compareTo(). Valid public IP addresses…
When was CVE-2026-44249 disclosed?
CVE-2026-44249 was first published in the National Vulnerability Database on June 8, 2026, with the most recent update on July 3, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-44249 actively exploited?
CVE-2026-44249 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 42.1% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-44249?
CVE-2026-44249 has a CVSS v3 base score of 8.1 (NVD).
How do I remediate CVE-2026-44249?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-44249, 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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