CVE-2026-11721

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-07-22. a secondary CVSS source baseline 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — Patch released this week
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.5Exploit: None knownExposed: 0

A fix is available — apply it.

It is possible for an attacker's zone to respond to a query with an RRSIG that has a smaller number of labels than the zone in which the RRSIG is contained. This causes named to produce a wildcard name for a zone that is shorter than the attacker's zone, which can result in cache poisoning. For this attack to have any effect, the resolver under attack must have set synth-from-dnssec yes; (which is the default). This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.

CVSS v3
7.5
EG Score
7.5(medium)
EG Risk
49(Track)
EG Risk 49/100SSVC: 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
Severity75% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
33%
KEV
Not listed

Published

July 22, 2026

Last Modified

July 22, 2026

Advisory Details (3)

Auto-updated Jul 22, 2026
No patch confirmed yet.
generic

CVE-2026-11721: Cache poisoning possible with label count discrepancy, RRSIG, and wildcards

https://kb.isc.org/docs/cve-2026-11721
generic

Index of /isc/bind9/9.21.24

https://downloads.isc.org/isc/bind9/9.21.24
generic

Index of /isc/bind9/9.20.26

https://downloads.isc.org/isc/bind9/9.20.26

Vendor Advisories for CVE-2026-11721(12)

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 / EcosystemFixed in / PatchReleasedSource
ubuntubind9-utils (1:9.20.24-1ubuntu0.2) @ resolute2026-09-16ubuntu
redhatrhcos-4.22.9.8.202609081748-02026-09-15redhat
redhatbind-32:9.11.4-26.P2.el7_9.212026-08-26redhat
redhatrhcos-4.22.9.8.202608191915-02026-08-25redhat
redhatbind-32:9.16.23-18.el9_4.122026-08-19redhat
redhatbind-32:9.16.23-31.el9_6.42026-08-17redhat
redhatbind9.18-32:9.18.29-14.el9_8.82026-08-17redhat
redhatbind-32:9.18.33-15.el10_2.102026-08-17redhat
redhatbind-32:9.11.36-16.el8_10.142026-08-13redhat
redhatbind9.16-32:9.16.23-0.22.el8_10.122026-08-13redhat
redhatbind-32:9.16.23-40.el9_8.82026-08-13redhat
redhatbind-main-9.20.26-0.1.hum12026-08-12redhat

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

(7 across 7 ecosystems)
Alpine:v3.22(1)
PackageVulnerable rangeFixed inDependents
bind—9.20.26-r0—
Alpine:v3.23(1)
PackageVulnerable rangeFixed inDependents
bind—9.20.26-r0—
Alpine:v3.24(1)
PackageVulnerable rangeFixed inDependents
bind—9.20.26-r0—
Debian:11(1)
PackageVulnerable rangeFixed inDependents
bind91:9.16.15-1 ... 1:9.16.50-1~deb11u5 (17 versions)1:9.16.50-1~deb11u6—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
bind91:9.18.12-1 ... 1:9.18.49-1~deb12u1 (16 versions)1:9.18.49-1~deb12u2—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
bind91:9.20.11-4 ... 1:9.20.26-1~deb13u1~bpo12+1 (21 versions)1:9.20.26-1~deb13u1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
bind91:9.20.11-4 ... 1:9.20.26-1~deb13u1~bpo12+1 (22 versions)1:9.20.26-1—

Weakness Classification(1)

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

Additional Vendor Advisories

(2)

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 29× in last 7d / 130× 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 252 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-11721?
CVE-2026-11721 is a high vulnerability published on July 22, 2026. It is possible for an attacker's zone to respond to a query with an RRSIG that has a smaller number of labels than the zone in which the RRSIG is contained. This causes named to produce a wildcard name for a zone that is shorter than the attacker's zone, which can result in cache poisoning. For…
When was CVE-2026-11721 disclosed?
CVE-2026-11721 was first published in the National Vulnerability Database on July 22, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-11721 actively exploited?
CVE-2026-11721 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 66.8% of all scored CVEs.
What is the CVSS score of CVE-2026-11721?
CVE-2026-11721 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-11721?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-11721, 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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