CVE-2026-47691

CRITICALNVD 10.010.0—
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 — 3 sources updated this week
10.0EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 10.0Exploit: None knownExposed: 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
10.0
EG Score
10.0(medium)
EG Risk
45(Track)
EG Risk 45/100SSVC: Track

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
Severity100% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
21%
KEV
Not listed

Published

June 8, 2026

Last Modified

July 21, 2026

Advisory Details (12)

Auto-updated Jul 21, 2026
Patch available. Sources: github_release, github, redhat.
redhat Patch Available

cve-details

https://access.redhat.com/security/cve/CVE-2026-47691
redhat Patch Available
https://access.redhat.com/errata/RHSA-2026:41951
redhat Patch Available
https://access.redhat.com/errata/RHSA-2026:37390
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
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
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-47691.json

Vendor Advisories for CVE-2026-47691(7)

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-dns2026-07-20redhat

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 12× in last 7d / 104× 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 170 total refreshes for this CVE.

  1. 2026-07-27 08:29 UTCVendor advisory
  2. 2026-07-27 02:01 UTCVendor advisory
  3. 2026-07-26 21:40 UTCEG score recompute
  4. 2026-07-26 21:40 UTCVendor advisory
  5. 2026-07-26 14:54 UTCEPSS rescore
  6. 2026-07-25 14:18 UTCEPSS rescore
  7. 2026-07-24 14:18 UTCEPSS rescore
  8. 2026-07-23 14:18 UTCEPSS rescore
  9. 2026-07-23 03:17 UTCEG score recompute
  10. 2026-07-22 14:08 UTCEPSS rescore
  11. 2026-07-21 15:24 UTCEPSS rescore
  12. 2026-07-20 17:08 UTCEPSS rescore
  13. 2026-07-19 14:31 UTCEPSS rescore
  14. 2026-07-19 02:29 UTCEPSS rescore
  15. 2026-07-18 10:04 UTCEPSS rescore
  16. 2026-07-16 17:03 UTCEPSS rescore
  17. 2026-07-16 09:38 UTCVendor advisory
  18. 2026-07-16 05:26 UTCVendor advisory
  19. 2026-07-16 00:28 UTCVendor advisory
  20. 2026-07-15 20:31 UTCVendor advisory
  21. 2026-07-15 16:57 UTCEPSS rescore
  22. 2026-07-15 02:26 UTCNVD updateCVSS v3 → 10 · severity → CRITICAL
  23. 2026-07-15 02:00 UTCEPSS rescore
  24. 2026-07-15 01:21 UTCMITRE cvelistV5CVSS v3 → 8.7 · severity → HIGH
  25. 2026-07-14 21:22 UTCVendor advisory
Show 75 more
  1. 2026-07-14 16:43 UTCVendor advisory
  2. 2026-07-14 12:46 UTCVendor advisory
  3. 2026-07-14 02:43 UTCVendor advisory
  4. 2026-07-13 22:30 UTCEPSS rescore
  5. 2026-07-13 06:13 UTCEPSS rescore
  6. 2026-07-12 09:53 UTCVendor advisory
  7. 2026-07-12 05:46 UTCEPSS rescore
  8. 2026-07-12 05:18 UTCVendor advisory
  9. 2026-07-12 00:38 UTCVendor advisory
  10. 2026-07-11 20:41 UTCVendor advisory
  11. 2026-07-11 16:40 UTCVendor advisory
  12. 2026-07-11 12:43 UTCVendor advisory
  13. 2026-07-11 08:46 UTCVendor advisory
  14. 2026-07-11 08:27 UTCEPSS rescore
  15. 2026-07-11 04:49 UTCVendor advisory
  16. 2026-07-10 21:24 UTCEG score recompute▲ 1.30
  17. 2026-07-10 21:24 UTCVendor advisory
  18. 2026-07-10 12:27 UTCNVD updateCVSS v3 → 10 · severity → CRITICAL
  19. 2026-07-09 19:10 UTCEPSS rescore
  20. 2026-07-09 03:59 UTCVendor advisory
  21. 2026-07-08 15:51 UTCVendor advisory
  22. 2026-07-08 15:16 UTCEPSS rescore
  23. 2026-07-08 02:38 UTCEG score recompute▼ 1.30
  24. 2026-07-08 02:38 UTCVendor advisory
  25. 2026-07-07 13:46 UTCEPSS rescore
  26. 2026-07-06 16:27 UTCEPSS rescore
  27. 2026-07-06 13:07 UTCMITRE cvelistV5CVSS v3 → 8.7 · severity → HIGH
  28. 2026-07-06 02:23 UTCEPSS rescore
  29. 2026-07-06 01:49 UTCVendor advisory
  30. 2026-07-05 21:52 UTCVendor advisory
  31. 2026-07-05 17:24 UTCVendor advisory
  32. 2026-07-05 02:30 UTCEPSS rescore
  33. 2026-07-05 00:53 UTCVendor advisory
  34. 2026-07-04 20:06 UTCVendor advisory
  35. 2026-07-04 14:48 UTCVendor advisory
  36. 2026-07-04 06:31 UTCEPSS rescore
  37. 2026-07-04 00:06 UTCVendor advisory
  38. 2026-07-03 20:07 UTCVendor advisory
  39. 2026-07-03 16:09 UTCVendor advisory
  40. 2026-07-03 09:21 UTCVendor advisory
  41. 2026-07-03 03:26 UTCVendor advisory
  42. 2026-07-02 23:29 UTCVendor advisory
  43. 2026-07-02 19:32 UTCVendor advisory
  44. 2026-07-02 15:36 UTCVendor advisory
  45. 2026-07-02 11:22 UTCVendor advisory
  46. 2026-07-02 06:53 UTCVendor advisory
  47. 2026-07-02 02:55 UTCVendor advisory
  48. 2026-07-01 22:57 UTCVendor advisory
  49. 2026-07-01 18:33 UTCVendor advisory
  50. 2026-07-01 15:07 UTCEPSS rescore
  51. 2026-07-01 14:36 UTCVendor advisory
  52. 2026-07-01 10:39 UTCVendor advisory
  53. 2026-07-01 06:30 UTCVendor advisory
  54. 2026-07-01 00:19 UTCVendor advisory
  55. 2026-06-30 23:22 UTCEPSS rescore
  56. 2026-06-30 20:21 UTCVendor advisory
  57. 2026-06-30 16:24 UTCVendor advisory
  58. 2026-06-30 07:21 UTCVendor advisory
  59. 2026-06-30 03:24 UTCVendor advisory
  60. 2026-06-29 23:28 UTCVendor advisory
  61. 2026-06-29 19:31 UTCVendor advisory
  62. 2026-06-29 15:34 UTCVendor advisory
  63. 2026-06-29 14:06 UTCEPSS rescore
  64. 2026-06-29 14:06 UTCEPSS rescore
  65. 2026-06-29 11:27 UTCVendor advisory
  66. 2026-06-29 07:30 UTCVendor advisory
  67. 2026-06-29 00:48 UTCVendor advisory
  68. 2026-06-28 20:50 UTCVendor advisory
  69. 2026-06-28 16:52 UTCVendor advisory
  70. 2026-06-28 14:07 UTCEPSS rescore
  71. 2026-06-28 12:55 UTCVendor advisory
  72. 2026-06-28 08:58 UTCVendor advisory
  73. 2026-06-28 05:01 UTCVendor advisory
  74. 2026-06-28 04:56 UTCEPSS rescore
  75. 2026-06-28 04:56 UTCEPSS rescore

Frequently asked(5)

What is CVE-2026-47691?
CVE-2026-47691 is a critical 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 21, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-47691 actively exploited?
CVE-2026-47691 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 79.1% of all scored CVEs.
What is the CVSS score of CVE-2026-47691?
CVE-2026-47691 has a CVSS v3 base score of 10.0 (NVD).
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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