CVE-2026-45416

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: 0.5%, top 63% 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

A fix is available — apply it.

Netty is a network application framework for development of protocol servers and clients. Prior to versions 4.1.135.Final and 4.2.15.Final, SslClientHelloHandler.decode() reads the 24-bit TLS handshake length and, when the ClientHello does not fit in the first record, eagerly allocates ctx.alloc().buffer(handshakeLength) (line 161). The guard at line 140 is handshakeLength > maxClientHelloLength && maxClientHelloLength != 0, and the commonly-used SniHandler/AbstractSniHandler constructors (SniHandler(Mapping), SniHandler(AsyncMapping), AbstractSniHandler()) pass maxClientHelloLength=0 and handshakeTimeoutMillis=0, so the length guard is disabled and no timeout is scheduled. A 16 MiB request exceeds the default pooled chunk size and becomes a huge/unpooled allocation performed immediately. The buffer is retained in the handler until the channel closes. Versions 4.1.135.Final and 4.2.15.Final patch the issue.

CVSS v3
7.5
EG Score
7.5(medium)
EPSS
38.5%
KEV
Not listed

Published

June 8, 2026

Last Modified

July 21, 2026

Advisory Details (3)

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

SNI handler pre-allocates up to 16 MiB from nine attacker bytes · Advisory · netty/netty · GitHub

https://github.com/netty/netty/security/advisories/GHSA-x4gw-5cx5-pgmh
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-2026-45416(8)

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-handler2026-07-09redhat
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(1)

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

Data Freshness Timeline

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

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-45416?
CVE-2026-45416 is a high vulnerability published on June 8, 2026. Netty is a network application framework for development of protocol servers and clients. Prior to versions 4.1.135.Final and 4.2.15.Final, SslClientHelloHandler.decode() reads the 24-bit TLS handshake length and, when the ClientHello does not fit in the first record, eagerly allocates…
When was CVE-2026-45416 disclosed?
CVE-2026-45416 was first published in the National Vulnerability Database on June 8, 2026, with the most recent update on July 21, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-45416 actively exploited?
CVE-2026-45416 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 38.5% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-45416?
CVE-2026-45416 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-45416?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-45416, 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.

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