CVE-2026-47691

HIGHPre-NVD 8.710.0▲
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 10.0 under NVD CVSS v3. EPSS exploit probability: 0.3%, top 79% 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 — Patch released this week
8.7
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 8.7Exploit: 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, Netty's DnsResolveContext insufficiently validates the bailiwick of NS records, enabling DNS Cache Poisoning. An attacker controlling an authoritative name server for a subdomain can poison the cache for parent domains (like .co.uk). In io.netty.resolver.dns.DnsResolveContext.AuthoritativeNameServerList#add method accepts any NS record from the AUTHORITY section as long as the record's name is a suffix of the questionName. Subsequently, the handleWithAdditional method caches the associated A records from the ADDITIONAL section directly into the authoritativeDnsServerCache under the parent domain's key. This bypasses standard bailiwick rules, where a server authoritative for a subdomain should not be trusted to provide authoritative records for its parent. The poisoned cache is then used for all future resolutions under the parent domain's key. Versions 4.1.135.Final and 4.2.15.Final patch the issue.

CVSS v3
8.7
EG Score
10.0(medium)
EPSS
21.0%
KEV
Not listed

Published

June 8, 2026

Last Modified

July 6, 2026

Advisory Details (10)

Auto-updated Jul 3, 2026
Patch available. Sources: github_release, github, redhat.
redhat Patch Available
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-47691.json
redhat Patch Available

2488439 – (CVE-2026-47691) CVE-2026-47691 io.netty/netty-resolver-dns: Netty has Insufficient Bailiwick Validation for NS Records

https://bugzilla.redhat.com/show_bug.cgi?id=2488439
redhat Patch Available

cve-details

https://access.redhat.com/security/cve/CVE-2026-47691
redhat Patch Available
https://access.redhat.com/errata/RHSA-2026:34608
redhat Patch Available
https://access.redhat.com/errata/RHSA-2026:26586
redhat Patch Available
https://access.redhat.com/errata/RHSA-2026:26018
redhat Patch Available
https://access.redhat.com/errata/RHSA-2026:26017
github Patch Available

Insufficient Bailiwick Validation for NS Records · Advisory · netty/netty · GitHub

https://github.com/netty/netty/security/advisories/GHSA-5pvg-856g-cp85
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-2026-47691(5)

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

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatnetty-resolver-dns2026-07-02redhat

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-resolver-dns4.1.0.Beta4 ... 4.1.99.Final (147 versions)4.1.135.Final—

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 59× in last 7d / 234× 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 234 total refreshes for this CVE.

  1. 2026-07-06 16:27 UTCEPSS rescore
  2. 2026-07-06 13:07 UTCMITRE cvelistV5CVSS v3 → 8.7 · severity → HIGH
  3. 2026-07-06 02:23 UTCEPSS rescore
  4. 2026-07-06 01:49 UTCEG score recompute
  5. 2026-07-06 01:49 UTCVendor advisory
  6. 2026-07-05 21:52 UTCEG score recompute
  7. 2026-07-05 21:52 UTCVendor advisory
  8. 2026-07-05 17:24 UTCEG score recompute
  9. 2026-07-05 17:24 UTCVendor advisory
  10. 2026-07-05 02:30 UTCEPSS rescore
  11. 2026-07-05 00:53 UTCEG score recompute
  12. 2026-07-05 00:53 UTCVendor advisory
  13. 2026-07-04 20:06 UTCEG score recompute
  14. 2026-07-04 20:06 UTCVendor advisory
  15. 2026-07-04 14:48 UTCEG score recompute
  16. 2026-07-04 14:48 UTCVendor advisory
  17. 2026-07-04 06:31 UTCEPSS rescore
  18. 2026-07-04 00:06 UTCEG score recompute
  19. 2026-07-04 00:06 UTCVendor advisory
  20. 2026-07-03 20:07 UTCEG score recompute
  21. 2026-07-03 20:07 UTCVendor advisory
  22. 2026-07-03 16:09 UTCEG score recompute
  23. 2026-07-03 16:09 UTCVendor advisory
  24. 2026-07-03 09:21 UTCEG score recompute
  25. 2026-07-03 09:21 UTCVendor advisory
Show 75 more
  1. 2026-07-03 03:26 UTCEG score recompute
  2. 2026-07-03 03:26 UTCVendor advisory
  3. 2026-07-02 23:29 UTCEG score recompute
  4. 2026-07-02 23:29 UTCVendor advisory
  5. 2026-07-02 19:32 UTCEG score recompute
  6. 2026-07-02 19:32 UTCVendor advisory
  7. 2026-07-02 15:36 UTCEG score recompute
  8. 2026-07-02 15:36 UTCVendor advisory
  9. 2026-07-02 11:22 UTCEG score recompute
  10. 2026-07-02 11:22 UTCVendor advisory
  11. 2026-07-02 06:53 UTCEG score recompute
  12. 2026-07-02 06:53 UTCVendor advisory
  13. 2026-07-02 02:55 UTCEG score recompute
  14. 2026-07-02 02:55 UTCVendor advisory
  15. 2026-07-01 22:57 UTCEG score recompute
  16. 2026-07-01 22:57 UTCVendor advisory
  17. 2026-07-01 18:33 UTCEG score recompute
  18. 2026-07-01 18:33 UTCVendor advisory
  19. 2026-07-01 15:07 UTCEPSS rescore
  20. 2026-07-01 14:36 UTCEG score recompute
  21. 2026-07-01 14:36 UTCVendor advisory
  22. 2026-07-01 10:39 UTCEG score recompute
  23. 2026-07-01 10:39 UTCVendor advisory
  24. 2026-07-01 06:30 UTCEG score recompute
  25. 2026-07-01 06:30 UTCVendor advisory
  26. 2026-07-01 00:19 UTCEG score recompute
  27. 2026-07-01 00:19 UTCVendor advisory
  28. 2026-06-30 23:22 UTCEPSS rescore
  29. 2026-06-30 20:21 UTCEG score recompute
  30. 2026-06-30 20:21 UTCVendor advisory
  31. 2026-06-30 16:24 UTCEG score recompute
  32. 2026-06-30 16:24 UTCVendor advisory
  33. 2026-06-30 07:21 UTCEG score recompute
  34. 2026-06-30 07:21 UTCVendor advisory
  35. 2026-06-30 03:24 UTCEG score recompute
  36. 2026-06-30 03:24 UTCVendor advisory
  37. 2026-06-29 23:28 UTCEG score recompute
  38. 2026-06-29 23:28 UTCVendor advisory
  39. 2026-06-29 19:31 UTCEG score recompute
  40. 2026-06-29 19:31 UTCVendor advisory
  41. 2026-06-29 15:34 UTCEG score recompute
  42. 2026-06-29 15:34 UTCVendor advisory
  43. 2026-06-29 14:06 UTCEPSS rescore
  44. 2026-06-29 14:06 UTCEPSS rescore
  45. 2026-06-29 11:27 UTCEG score recompute
  46. 2026-06-29 11:27 UTCVendor advisory
  47. 2026-06-29 07:30 UTCEG score recompute
  48. 2026-06-29 07:30 UTCVendor advisory
  49. 2026-06-29 00:48 UTCEG score recompute
  50. 2026-06-29 00:48 UTCVendor advisory
  51. 2026-06-28 20:50 UTCEG score recompute
  52. 2026-06-28 20:50 UTCVendor advisory
  53. 2026-06-28 16:52 UTCEG score recompute
  54. 2026-06-28 16:52 UTCVendor advisory
  55. 2026-06-28 14:07 UTCEPSS rescore
  56. 2026-06-28 12:55 UTCEG score recompute
  57. 2026-06-28 12:55 UTCVendor advisory
  58. 2026-06-28 08:58 UTCEG score recompute
  59. 2026-06-28 08:58 UTCVendor advisory
  60. 2026-06-28 05:01 UTCEG score recompute
  61. 2026-06-28 05:01 UTCVendor advisory
  62. 2026-06-28 04:56 UTCEPSS rescore
  63. 2026-06-28 04:56 UTCEPSS rescore
  64. 2026-06-28 01:04 UTCEG score recompute
  65. 2026-06-28 01:04 UTCVendor advisory
  66. 2026-06-27 21:03 UTCEG score recompute
  67. 2026-06-27 21:03 UTCVendor advisory
  68. 2026-06-27 17:05 UTCEG score recompute
  69. 2026-06-27 17:05 UTCVendor advisory
  70. 2026-06-27 13:08 UTCEG score recompute
  71. 2026-06-27 13:08 UTCVendor advisory
  72. 2026-06-27 09:11 UTCEG score recompute
  73. 2026-06-27 09:11 UTCVendor advisory
  74. 2026-06-27 05:13 UTCEG score recompute
  75. 2026-06-27 05:13 UTCVendor advisory

Frequently asked(5)

What is CVE-2026-47691?
CVE-2026-47691 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, Netty's DnsResolveContext insufficiently validates the bailiwick of NS records, enabling DNS Cache Poisoning. An attacker controlling an authoritative name…
When was CVE-2026-47691 disclosed?
CVE-2026-47691 was first published in the National Vulnerability Database on June 8, 2026, with the most recent update on July 6, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-47691 actively exploited?
CVE-2026-47691 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 21.0% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-47691?
CVE-2026-47691 has a CVSS v4.0 base score of 8.7 (CNA self-assessment; NVD's own analysis pending). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 10.0.
How do I remediate CVE-2026-47691?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-47691, 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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