CVE-2026-42579

CRITICALNVD 9.17.5▼
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under NVD CVSS v3. EPSS exploit probability: 0.5%, top 60% 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
Trending — 3 sources updated this weekElevated
9.1
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 1%CVSS: 9.1Exploit: NoneExposed: 0

A fix is available — apply it.

Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Netty's DNS codec does not enforce RFC 1035 domain name constraints during either encoding or decoding. This creates a bidirectional attack surface: malicious DNS responses can exploit the decoder, and user-influenced hostnames can exploit the encoder. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.

CVSS v3
9.1
EG Score
7.5(medium)
EPSS
56.9%
KEV
Not listed

Published

May 13, 2026

Last Modified

July 10, 2026

Advisory Details (1)

Auto-updated May 13, 2026
🔬 Proof of concept available. Patch available. Sources: github.
github Patch Available🟡 PoC Available

DNS Codec Input Validation Bypass in Netty (Encoder + Decoder) · Advisory · netty/netty · GitHub

https://github.com/netty/netty/security/advisories/GHSA-cm33-6792-r9fm

Vendor Advisories for CVE-2026-42579(7)

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
ubuntulibnetty-java (1:4.0.34-1ubuntu0.1~esm4) @ xenial2026-06-29ubuntu
redhatcryostat/jfr-datasource-rhel9:4.2.0-102026-06-22redhat
redhatpatch2026-06-10redhat
redhatdevspaces/server-rhel9:17806949942026-06-10redhat
redhatnetty-codec-dns2026-06-10redhat

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-codec-dns4.1.0.Beta1 ... 4.1.99.Final (148 versions)4.1.133.Final—

Weakness Classification(4)

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 13× in last 7d / 68× 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 134 total refreshes for this CVE.

  1. 2026-07-11 08:27 UTCEPSS rescore
  2. 2026-07-10 12:26 UTCNVD updateCVSS v3 → 9.1 · severity → CRITICAL
  3. 2026-07-10 12:12 UTCMITRE cvelistV5CVSS v3 → 7.5 · severity → HIGH
  4. 2026-07-09 19:10 UTCEPSS rescore
  5. 2026-07-09 13:52 UTCNVD updateCVSS v3 → 9.1 · severity → CRITICAL
  6. 2026-07-08 15:15 UTCEPSS rescore
  7. 2026-07-08 12:47 UTCMITRE cvelistV5CVSS v3 → 7.5 · severity → HIGH
  8. 2026-07-07 13:46 UTCEPSS rescore
  9. 2026-07-06 16:27 UTCEPSS rescore
  10. 2026-07-06 16:27 UTCEPSS rescore
  11. 2026-07-06 02:23 UTCEPSS rescore
  12. 2026-07-06 02:23 UTCEPSS rescore
  13. 2026-07-05 02:30 UTCEPSS rescore
  14. 2026-07-04 06:31 UTCEPSS rescore
  15. 2026-07-01 15:06 UTCEPSS rescore
  16. 2026-06-30 23:22 UTCEPSS rescore
  17. 2026-06-30 04:33 UTCNVD updateCVSS v3 → 9.1 · severity → CRITICAL
  18. 2026-06-29 22:13 UTCEG score recompute
  19. 2026-06-29 22:13 UTCVendor advisory
  20. 2026-06-29 14:06 UTCEPSS rescore
  21. 2026-06-28 14:07 UTCEPSS rescore
  22. 2026-06-28 11:26 UTCEG score recompute
  23. 2026-06-28 11:26 UTCVendor advisory
  24. 2026-06-28 04:56 UTCEPSS rescore
  25. 2026-06-27 23:23 UTCEG score recompute
Show 75 more
  1. 2026-06-27 23:23 UTCVendor advisory
  2. 2026-06-27 08:09 UTCEG score recompute
  3. 2026-06-27 08:09 UTCVendor advisory
  4. 2026-06-27 03:08 UTCEPSS rescore
  5. 2026-06-26 20:29 UTCEG score recompute
  6. 2026-06-26 20:29 UTCVendor advisory
  7. 2026-06-25 19:35 UTCEG score recompute
  8. 2026-06-25 19:35 UTCVendor advisory
  9. 2026-06-25 13:49 UTCEPSS rescore
  10. 2026-06-25 13:49 UTCEPSS rescore
  11. 2026-06-24 14:05 UTCEPSS rescore
  12. 2026-06-23 21:33 UTCEPSS rescore
  13. 2026-06-22 14:25 UTCEPSS rescore
  14. 2026-06-22 14:25 UTCEPSS rescore
  15. 2026-06-21 14:56 UTCEPSS rescore
  16. 2026-06-21 14:56 UTCEPSS rescore
  17. 2026-06-21 01:59 UTCEPSS rescore
  18. 2026-06-19 19:25 UTCEPSS rescore
  19. 2026-06-18 17:52 UTCEPSS rescore
  20. 2026-06-18 17:52 UTCEPSS rescore
  21. 2026-06-17 17:53 UTCEPSS rescore
  22. 2026-06-17 14:27 UTCEG score recompute
  23. 2026-06-17 14:27 UTCVendor advisory
  24. 2026-06-16 22:31 UTCEG score recompute
  25. 2026-06-16 22:31 UTCVendor advisory
  26. 2026-06-16 17:52 UTCEPSS rescore
  27. 2026-06-16 00:39 UTCEG score recompute
  28. 2026-06-16 00:39 UTCVendor advisory
  29. 2026-06-15 17:49 UTCEPSS rescore
  30. 2026-06-14 22:45 UTCEG score recompute
  31. 2026-06-14 22:45 UTCVendor advisory
  32. 2026-06-14 11:14 UTCEG score recompute
  33. 2026-06-14 11:14 UTCVendor advisory
  34. 2026-06-13 23:43 UTCEG score recompute
  35. 2026-06-13 23:43 UTCVendor advisory
  36. 2026-06-13 06:32 UTCEG score recompute
  37. 2026-06-13 06:32 UTCVendor advisory
  38. 2026-06-12 23:12 UTCEPSS rescore
  39. 2026-06-12 23:12 UTCEPSS rescore
  40. 2026-06-12 18:58 UTCEG score recompute
  41. 2026-06-12 18:58 UTCVendor advisory
  42. 2026-06-12 07:26 UTCEG score recompute
  43. 2026-06-12 07:26 UTCVendor advisory
  44. 2026-06-11 19:54 UTCEG score recompute
  45. 2026-06-11 19:54 UTCVendor advisory
  46. 2026-06-11 14:00 UTCEPSS rescore
  47. 2026-06-11 08:23 UTCEG score recompute
  48. 2026-06-11 08:23 UTCVendor advisory
  49. 2026-06-10 22:18 UTCEPSS rescore
  50. 2026-06-10 20:52 UTCEG score recompute
  51. 2026-06-10 20:52 UTCVendor advisory
  52. 2026-06-10 13:22 UTCEPSS rescore
  53. 2026-06-10 13:22 UTCEPSS rescore
  54. 2026-06-10 09:19 UTCEG score recompute
  55. 2026-06-10 09:19 UTCVendor advisory
  56. 2026-06-09 21:48 UTCEG score recompute
  57. 2026-06-09 09:51 UTCEG score recompute
  58. 2026-06-09 09:51 UTCVendor advisory
  59. 2026-06-08 22:20 UTCEG score recompute
  60. 2026-06-08 22:20 UTCVendor advisory
  61. 2026-06-08 14:17 UTCEPSS rescore
  62. 2026-06-08 14:17 UTCEPSS rescore
  63. 2026-06-08 10:48 UTCEG score recompute
  64. 2026-06-07 23:17 UTCEG score recompute
  65. 2026-06-07 15:25 UTCEPSS rescore
  66. 2026-06-07 15:25 UTCEPSS rescore
  67. 2026-06-07 11:46 UTCEG score recompute
  68. 2026-06-07 00:15 UTCEG score recompute
  69. 2026-06-06 13:47 UTCEPSS rescore
  70. 2026-06-06 13:47 UTCEPSS rescore
  71. 2026-06-06 12:44 UTCEG score recompute
  72. 2026-06-06 01:11 UTCEG score recompute
  73. 2026-06-05 22:47 UTCEPSS rescore
  74. 2026-06-05 13:40 UTCEG score recompute
  75. 2026-06-05 06:10 UTCEPSS rescore

Frequently asked(5)

What is CVE-2026-42579?
CVE-2026-42579 is a critical vulnerability published on May 13, 2026. Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Netty's DNS codec does not enforce RFC 1035 domain name constraints during either encoding or decoding. This creates a bidirectional attack surface: malicious DNS responses can exploit the…
When was CVE-2026-42579 disclosed?
CVE-2026-42579 was first published in the National Vulnerability Database on May 13, 2026, with the most recent update on July 10, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-42579 actively exploited?
CVE-2026-42579 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 56.9% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-42579?
CVE-2026-42579 has a CVSS v3 base score of 9.1 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 7.5.
How do I remediate CVE-2026-42579?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-42579, 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

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-42579

Explore →

Is Your Infrastructure Affected by CVE-2026-42579?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs