CVE-2026-5947

MEDIUMNVD 5.97.5▲
EchelonGraph scoreMEDIUM confidence

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-05-20. NVD baseline CVSS 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
5.9
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 1%CVSS: 5.9Exploit: NoneExposed: 0

A fix is available — apply it.

Undefined behavior may result due to a race condition leading to a use-after-free violation. If BIND receives an incoming DNS message signed with SIG(0), it begins work to validate that signature. If, during that validation, the "recursive-clients" limit is reached (as would occur during a query flood), and that same DNS message is discarded per the limit, there is a brief window of time while the SIG(0) validation may attempt to read the now-discarded DNS message. This issue affects BIND 9 versions 9.20.0 through 9.20.22, 9.21.0 through 9.21.21, and 9.20.9-S1 through 9.20.22-S1. BIND 9 versions 9.18.28 through 9.18.49 and 9.18.28-S1 through 9.18.49-S1 are NOT affected.

CVSS v3
5.9
EG Score
7.5(medium)
EPSS
69.0%
KEV
Not listed

Published

May 20, 2026

Last Modified

June 30, 2026

Advisory Details (3)

Auto-updated Jun 6, 2026
No patch confirmed yet.
generic

CVE-2026-5947: SIG(0) validation during query flood may lead to undefined behavior

https://kb.isc.org/docs/cve-2026-5947
generic

Index of /isc/bind9/9.21.22

https://downloads.isc.org/isc/bind9/9.21.22
generic

Index of /isc/bind9/9.20.23

https://downloads.isc.org/isc/bind9/9.20.23

Vendor Advisories for CVE-2026-5947(3)

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

Patch Availability(2)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntubind9-utils (1:9.20.18-1ubuntu2.1) @ resolute2026-06-29ubuntu
redhatbind-main-9.18.48-1.1.hum12026-04-10redhat

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.

Weakness Classification(3)

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 11× in last 7d / 94× 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 189 total refreshes for this CVE.

  1. 2026-07-12 05:46 UTCEPSS rescore
  2. 2026-07-11 08:27 UTCEPSS rescore
  3. 2026-07-11 08:27 UTCEPSS rescore
  4. 2026-07-09 19:10 UTCEPSS rescore
  5. 2026-07-09 19:10 UTCEPSS rescore
  6. 2026-07-08 15:16 UTCEPSS rescore
  7. 2026-07-08 15:16 UTCEPSS rescore
  8. 2026-07-06 16:27 UTCEPSS rescore
  9. 2026-07-06 16:27 UTCEPSS rescore
  10. 2026-07-06 02:23 UTCEPSS rescore
  11. 2026-07-06 02:23 UTCEPSS rescore
  12. 2026-07-05 02:31 UTCEPSS rescore
  13. 2026-07-05 02:30 UTCEPSS rescore
  14. 2026-07-04 06:31 UTCEPSS rescore
  15. 2026-07-04 06:31 UTCEPSS rescore
  16. 2026-07-01 15:07 UTCEPSS rescore
  17. 2026-06-30 23:22 UTCEPSS rescore
  18. 2026-06-30 04:33 UTCNVD updateCVSS v3 → 5.9 · severity → MEDIUM
  19. 2026-06-29 20:29 UTCEG score recompute
  20. 2026-06-29 20:29 UTCVendor advisory
  21. 2026-06-29 20:29 UTCGHSA enrichment
  22. 2026-06-29 14:06 UTCEPSS rescore
  23. 2026-06-28 09:21 UTCEG score recompute
  24. 2026-06-28 09:21 UTCVendor advisory
  25. 2026-06-28 09:21 UTCGHSA enrichment
Show 75 more
  1. 2026-06-28 04:56 UTCEPSS rescore
  2. 2026-06-27 20:48 UTCEG score recompute
  3. 2026-06-27 20:48 UTCVendor advisory
  4. 2026-06-27 20:48 UTCGHSA enrichment
  5. 2026-06-27 08:05 UTCEG score recompute
  6. 2026-06-27 08:05 UTCVendor advisory
  7. 2026-06-27 08:05 UTCGHSA enrichment
  8. 2026-06-27 03:08 UTCEPSS rescore
  9. 2026-06-26 19:34 UTCEG score recompute
  10. 2026-06-26 19:34 UTCVendor advisory
  11. 2026-06-26 19:34 UTCGHSA enrichment
  12. 2026-06-26 04:07 UTCEG score recompute
  13. 2026-06-26 04:07 UTCVendor advisory
  14. 2026-06-26 04:07 UTCGHSA enrichment
  15. 2026-06-25 15:35 UTCEG score recompute
  16. 2026-06-25 15:35 UTCVendor advisory
  17. 2026-06-25 15:35 UTCGHSA enrichment
  18. 2026-06-25 13:50 UTCEPSS rescore
  19. 2026-06-24 14:05 UTCEPSS rescore
  20. 2026-06-23 21:33 UTCEPSS rescore
  21. 2026-06-23 21:33 UTCEPSS rescore
  22. 2026-06-22 14:25 UTCEPSS rescore
  23. 2026-06-22 14:25 UTCEPSS rescore
  24. 2026-06-21 14:56 UTCEPSS rescore
  25. 2026-06-21 14:56 UTCEPSS rescore
  26. 2026-06-21 01:59 UTCEPSS rescore
  27. 2026-06-21 01:59 UTCEPSS rescore
  28. 2026-06-19 19:26 UTCEPSS rescore
  29. 2026-06-19 19:26 UTCEPSS rescore
  30. 2026-06-18 17:52 UTCEPSS rescore
  31. 2026-06-18 17:52 UTCEPSS rescore
  32. 2026-06-17 23:56 UTCEG score recompute
  33. 2026-06-17 23:56 UTCVendor advisory
  34. 2026-06-17 23:56 UTCGHSA enrichment
  35. 2026-06-17 17:53 UTCEPSS rescore
  36. 2026-06-17 11:26 UTCEG score recompute
  37. 2026-06-17 11:26 UTCVendor advisory
  38. 2026-06-17 11:26 UTCGHSA enrichment
  39. 2026-06-16 20:13 UTCEG score recompute
  40. 2026-06-16 20:13 UTCVendor advisory
  41. 2026-06-16 20:13 UTCGHSA enrichment
  42. 2026-06-16 17:53 UTCEPSS rescore
  43. 2026-06-16 04:53 UTCEG score recompute
  44. 2026-06-16 04:53 UTCVendor advisory
  45. 2026-06-16 04:52 UTCGHSA enrichment
  46. 2026-06-15 17:49 UTCEPSS rescore
  47. 2026-06-15 17:49 UTCEPSS rescore
  48. 2026-06-15 15:51 UTCEG score recompute
  49. 2026-06-15 15:51 UTCVendor advisory
  50. 2026-06-15 15:51 UTCGHSA enrichment
  51. 2026-06-14 23:31 UTCEG score recompute
  52. 2026-06-14 23:31 UTCVendor advisory
  53. 2026-06-14 23:31 UTCGHSA enrichment
  54. 2026-06-14 23:18 UTCEPSS rescore
  55. 2026-06-14 11:00 UTCEG score recompute
  56. 2026-06-14 11:00 UTCVendor advisory
  57. 2026-06-14 10:59 UTCGHSA enrichment
  58. 2026-06-13 23:00 UTCEPSS rescore
  59. 2026-06-13 22:28 UTCEG score recompute
  60. 2026-06-13 22:28 UTCVendor advisory
  61. 2026-06-13 22:28 UTCGHSA enrichment
  62. 2026-06-13 02:50 UTCEG score recompute
  63. 2026-06-13 02:50 UTCVendor advisory
  64. 2026-06-13 02:50 UTCGHSA enrichment
  65. 2026-06-12 23:12 UTCEPSS rescore
  66. 2026-06-12 23:12 UTCEPSS rescore
  67. 2026-06-12 14:17 UTCEG score recompute
  68. 2026-06-12 14:17 UTCVendor advisory
  69. 2026-06-12 14:17 UTCGHSA enrichment
  70. 2026-06-12 01:46 UTCEG score recompute
  71. 2026-06-12 01:46 UTCVendor advisory
  72. 2026-06-12 01:46 UTCGHSA enrichment
  73. 2026-06-11 14:00 UTCEPSS rescore
  74. 2026-06-11 13:15 UTCEG score recompute
  75. 2026-06-11 13:15 UTCVendor advisory

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-5947?
CVE-2026-5947 is a medium vulnerability published on May 20, 2026. Undefined behavior may result due to a race condition leading to a use-after-free violation. If BIND receives an incoming DNS message signed with SIG(0), it begins work to validate that signature. If, during that validation, the "recursive-clients" limit is reached (as would occur during a query…
When was CVE-2026-5947 disclosed?
CVE-2026-5947 was first published in the National Vulnerability Database on May 20, 2026, with the most recent update on June 30, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-5947 actively exploited?
CVE-2026-5947 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 69.0% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-5947?
CVE-2026-5947 has a CVSS v3 base score of 5.9 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 7.5.
How do I remediate CVE-2026-5947?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-5947, 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

Explore the affected products and dependency analysis for CVE-2026-5947

Explore →

Is Your Infrastructure Affected by CVE-2026-5947?

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

Start Free Scan →Browse All CVEs