CVE-2026-42579

CRITICALNVD 9.19.1—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.1 under NVD CVSS v3. EPSS exploit probability: 1.0%, top 39% 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
Elevated
9.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.8%CVSS: 9.1Exploit: Elevated riskExposed services: Not assessed

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
9.1CRITICALmedium confidence
EG Risk
72
EG Risk 72/100

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
Severity91% × 45%
Exploitation40% × 40%
Automatability100% × 15%
EPSS PROB
0.8%
EPSS %ILE
56th
KEV
Not listed

Published

May 13, 2026

Last Modified

September 18, 2026

Advisory Details (11)

Auto-updated Sep 15, 2026
🔬 Proof of concept available. Patch available. Sources: github, redhat.
redhatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:53806
redhatMentions a patch (unverified)

Affected: Red Hat Enterprise Linux 7. Red Hat Product Security has rated

https://access.redhat.com/errata/RHSA-2026:53644
redhatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:49700
redhatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:37390
redhatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:36820
redhatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:28010
redhatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:25123
redhatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:24502
redhatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:23808
githubMentions a patch (unverified)🟡 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
redhatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:54435

Vendor Advisories for CVE-2026-42579(20)

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

Patch Availability(12)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubuntulibnetty-java (1:4.0.34-1ubuntu0.1~esm4) @ xenial2026-09-18ubuntu
redhatrhoai/odh-trustyai-service-rhel9:17881986812026-09-08redhat
redhatnetty-codec-dns2026-08-12redhat
redhateap7-wildfly-0:7.4.25-2.GA_redhat_00001.1.el8eap2026-08-11redhat
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.el7eap2026-08-11redhat
redhateap8-wildfly-0:8.1.7.1-1.GA_redhat_00004.1.el9eap2026-08-03redhat
redhatio.netty/netty-codec-dns:4.1.135.Final-redhat-000012026-08-03redhat
redhatdevspaces/multicluster-redirector-rhel9:17829890272026-07-08redhat
redhatcryostat/jfr-datasource-rhel9:4.2.0-102026-06-22redhat
redhatdevspaces/server-rhel9:17806949942026-06-10redhat
redhatpatch2026-06-10redhat

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

(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-codec-dns4.1.0.Beta1 ... 4.1.99.Final (148 versions)
  • 4.2.0.Alpha1 up to 4.2.13.Final: fixed in 4.2.13.Final
  • every version up to 4.1.133.Final: fixed in 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 7× in last 7d / 26× 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 277 total refreshes for this CVE.

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

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

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 on May 13, 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-2026-42579 actively exploited?
CVE-2026-42579 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.8% probability of exploitation in the next 30 days (56th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-42579?
CVE-2026-42579 has a CVSS v3 base score of 9.1 (NVD).
How do I remediate CVE-2026-42579?
A fix for CVE-2026-42579 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-42579 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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