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: 1.0%, top 38% 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
8.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1.3%CVSS: 8.1Exploit: None knownExposed services: Not assessed

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
8.1HIGHmedium confidence
EG Risk
37
EG Risk 37/100

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
Severity81% × 45%
Exploitation1% × 40%
Automatability0% × 15%
EPSS PROB
1.3%
EPSS %ILE
69th
KEV
Not listed

Published

June 8, 2026

Last Modified

September 18, 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(20)

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

Patch Availability(11)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatnetty-handler2026-09-10redhat
redhatrhoai/odh-trustyai-service-rhel9:17881986812026-09-08redhat
redhateap7-wildfly-0:7.4.25-2.GA_redhat_00001.1.el7eap2026-08-11redhat
redhateap7-wildfly-0:7.4.25-2.GA_redhat_00001.1.el9eap2026-08-11redhat
redhateap7-wildfly-0:7.4.25-2.GA_redhat_00001.1.el8eap2026-08-11redhat
redhatio.netty/netty-handler:4.1.135.Final-redhat-000012026-08-03redhat
redhateap8-wildfly-0:8.1.7.1-1.GA_redhat_00004.1.el9eap2026-08-03redhat
redhatdevspaces/jetbrains-ide-rhel9:17848305522026-07-29redhat
redhatcryostat/jfr-datasource-rhel9:4.2.0-132026-07-29redhat
redhatdevspaces/pluginregistry-rhel9:17829893672026-07-08redhat
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

(5 across 5 ecosystems)
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
netty1:4.1.48-10 ... 1:4.1.48-9 (16 versions)
  • every version on: no fix on record
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
netty1:4.1.48-10 ... 1:4.1.48-9 (12 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
netty1:4.1.48-10 ... 1:4.1.48-16 (8 versions)
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
netty1:4.1.48-10 ... 1:4.1.48-16 (7 versions)
  • every version on: no fix on record
—
Maven(1)
PackageVulnerable rangeFix by version rangeDependents
io.netty:netty-handler4.0.0.Alpha1 ... 4.1.99.Final (228 versions)
  • 4.2.0.Final up to 4.2.15.Final: fixed in 4.2.15.Final
  • every version up to 4.1.135.Final: fixed in 4.1.135.Final
—

Weakness Classification(3)

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

Additional Vendor Advisories

(2)

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 4× in last 7d / 44× 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 297 total refreshes for this CVE.

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

Related CVEs(same product + same vendor + same CWE)

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 on June 8, 2026, with the most recent update on September 18, 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 1.3% probability of exploitation in the next 30 days (69th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-44249?
CVE-2026-44249 has a CVSS base score of 8.1 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-44249?
A fix for CVE-2026-44249 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-44249 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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