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
Trending — 4 sources updated 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: 1%CVSS: 7.5Exploit: None knownExposed: 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)
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%
Exploitation1% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
55%
KEV
Not listed

Published

May 20, 2026

Last Modified

August 25, 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(5)

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) @ resolute2026-08-25ubuntu
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.

Affected Packages

(5 across 5 ecosystems)
Alpine:v3.24(1)
PackageVulnerable rangeFixed inDependents
unbound—1.25.1-r0—
Debian:11(1)
PackageVulnerable rangeFixed inDependents
unbound1.13.1-1 ... 1.25.2-1 (47 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
unbound1.17.1-2 ... 1.25.2-1 (23 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
unbound1.22.0-2, 1.22.0-2+deb13u1, 1.22.0-2+deb13u21.22.0-2+deb13u3—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
unbound1.22.0-2 ... 1.25.0-1 (8 versions)1.25.1-1—

Weakness Classification(2)

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 17× in last 7d / 107× 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 279 total refreshes for this CVE.

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

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 August 25, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-42944 actively exploited?
CVE-2026-42944 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 44.8% of all scored CVEs.
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

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