CVE-2026-42387

MEDIUMPre-NVD 5.95.9—
EchelonGraph scoreMEDIUM confidence

Score 5.9 from GitHub Security Advisory published 2026-06-25. a secondary CVSS source baseline 5.9; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
5.9EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.9Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

A malicious authoritative server can send a crafted zone via the ZoneToCache function that leads to a crash of the Recursor due to insuffcient input validation.

CVSS v3
5.9
EG Score
5.9(medium)
EG Risk
31(Track)
EG Risk 31/100SSVC: 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
Severity59% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
32%
KEV
Not listed

Published

June 25, 2026

Last Modified

June 25, 2026

References (1)

Vendor Advisories for CVE-2026-42387(1)

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

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
pdns-recursor4.4.2-3 ... 5.4.4-1 (65 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
pdns-recursor4.8.4-1 ... 5.4.5-1 (51 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
pdns-recursor5.2.4-2 ... 5.2.9-0+deb13u1 (7 versions)5.2.11-0+deb13u1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
pdns-recursor5.2.4-2 ... 5.4.2-2 (17 versions)5.4.3-1—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 6× in last 7d / 51× 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 153 total refreshes for this CVE.

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

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-42387?
CVE-2026-42387 is a medium vulnerability published on June 25, 2026. A malicious authoritative server can send a crafted zone via the ZoneToCache function that leads to a crash of the Recursor due to insuffcient input validation.
When was CVE-2026-42387 disclosed?
CVE-2026-42387 was first published in the National Vulnerability Database on June 25, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-42387 actively exploited?
CVE-2026-42387 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 68.0% of all scored CVEs.
What is the CVSS score of CVE-2026-42387?
CVE-2026-42387 has a CVSS v3 base score of 5.9 (NVD).
How do I remediate CVE-2026-42387?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-42387, 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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