CVE-2026-44621

MEDIUMPre-NVD 5.95.9—
EchelonGraph scoreMEDIUM confidence

Score 5.9 from GitHub Security Advisory published 2026-07-22. a secondary CVSS source baseline 5.9; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
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.

With NLnet Labs Unbound up to and including version 1.25.1, applications using libunbound and configured with 'unwanted-reply-threshold', could eventually be abruptly terminated if the threshold is reached and libunbound needs to call 'libworker_alloc_cleanup' since the function is absent from the function call allow list. When an application using libunbound sets 'unwanted-reply-threshold' to any non-zero value and the iterator queries an authoritative that replies with enough wrong-transaction-ID UDP datagrams to cross the threshold, the 'libworker_alloc_cleanup' will eventually be called. Since the function is absent from the function call allow list, this leads to a fatal exit of libunbound and eventual termination of the embedding application.Unbound itself is not affected since its relevant function 'worker_alloc_cleanup' is registed in the allow list and proceeds to perform the documented cache flush.

CVSS v3
5.9
EG Score
5.9(medium)
EG Risk
27(Track)
EG Risk 27/100SSVC: 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%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
16%
KEV
Not listed

Published

July 22, 2026

Last Modified

July 24, 2026

Advisory Details (1)

Auto-updated Jul 22, 2026
No patch confirmed yet.
generic
https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-44621.txt

Vendor Advisories for CVE-2026-44621(2)

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

Affected Packages

(5 across 5 ecosystems)
Alpine:v3.24(1)
PackageVulnerable rangeFixed inDependents
unbound—1.25.2-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 ... 1.26.0-2 (25 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
unbound1.22.0-2 ... 1.26.0-2 (15 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
unbound1.22.0-2 ... 1.25.1-1 (9 versions)1.25.2-1—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 19× in last 7d / 84× 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 174 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-44621?
CVE-2026-44621 is a medium vulnerability published on July 22, 2026. With NLnet Labs Unbound up to and including version 1.25.1, applications using libunbound and configured with 'unwanted-reply-threshold', could eventually be abruptly terminated if the threshold is reached and libunbound needs to call 'libworkeralloccleanup' since the function is absent from the…
When was CVE-2026-44621 disclosed?
CVE-2026-44621 was first published in the National Vulnerability Database on July 22, 2026, with the most recent update on July 24, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-44621 actively exploited?
CVE-2026-44621 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 83.9% of all scored CVEs.
What is the CVSS score of CVE-2026-44621?
CVE-2026-44621 has a CVSS v3 base score of 5.9 (NVD).
How do I remediate CVE-2026-44621?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-44621, 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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