CVE-2026-42944

HIGHNVD 7.57.5—
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
7.5
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 1%CVSS: 7.5Exploit: NoneExposed: 0

A fix is available — apply it.

NLnet Labs Unbound 1.14.0 up to and including version 1.25.0 has a vulnerability that results in heap overflow when encoding multiple NSID and/or DNS Cookie EDNS and/or EDNS Padding options in the reply packet. The relevant options ('nsid', 'answer-cookie', 'pad-responses' (default)) need to be enabled for the vulnerability to be exploited. An adversary who can query Unbound can exploit the vulnerability by attaching multiple NSID and/or DNS Cookie EDNS and/or EDNS Padding options to the query. A flaw in the size calculation of the EDNS field truncates the correct value which allows the encoder to overflow the available space when writing. Those two combined lead to a heap overflow write of Unbound controlled data and eventually a crash. Unbound 1.25.1 contains a patch with a fix to de-duplicate the EDNS options and a fix to prevent truncation of the EDNS field size calculation.

CVSS v3
7.5
EG Score
7.5(medium)
EPSS
53.6%
KEV
Not listed

Published

May 20, 2026

Last Modified

June 30, 2026

Advisory Details (1)

Auto-updated May 20, 2026
No patch confirmed yet.
generic
https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-42944.txt

Vendor Advisories for CVE-2026-42944(4)

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

Patch Availability(5)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntuunbound-host (1.24.2-1ubuntu2.1) @ resolute2026-06-29ubuntu
redhatunbound-0:1.16.2-5.11.el8_102026-06-08redhat
redhatunbound-0:1.24.2-3.el9_8.12026-06-08redhat
redhatunbound-0:1.24.2-7.el10_2.12026-06-04redhat
redhatunbound-main-1.25.1-0.1.hum12026-05-20redhat

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.

Weakness Classification(2)

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

Additional Vendor Advisories

(3)

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 8× in last 7d / 90× 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 193 total refreshes for this CVE.

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

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-42944?
CVE-2026-42944 is a high vulnerability published on May 20, 2026. NLnet Labs Unbound 1.14.0 up to and including version 1.25.0 has a vulnerability that results in heap overflow when encoding multiple NSID and/or DNS Cookie EDNS and/or EDNS Padding options in the reply packet. The relevant options ('nsid', 'answer-cookie', 'pad-responses' (default)) need to be…
When was CVE-2026-42944 disclosed?
CVE-2026-42944 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-2026-42944 actively exploited?
CVE-2026-42944 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 53.6% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-42944?
CVE-2026-42944 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-42944?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-42944, 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-2026-42944

Explore →

Is Your Infrastructure Affected by CVE-2026-42944?

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

Start Free Scan →Browse All CVEs