CVE-2026-44621

MEDIUMPre-NVD 5.95.9—
EchelonGraph scoreHIGH 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 — 5 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(high)
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
17%
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.

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 22× in last 7d / 22× 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.

  1. 2026-07-28 07:58 UTCEG score recompute
  2. 2026-07-28 07:58 UTCVendor advisory
  3. 2026-07-28 07:58 UTCGHSA enrichment
  4. 2026-07-27 14:13 UTCEPSS rescore
  5. 2026-07-27 05:44 UTCEG score recompute
  6. 2026-07-27 05:44 UTCVendor advisory
  7. 2026-07-27 05:44 UTCGHSA enrichment
  8. 2026-07-26 14:54 UTCEPSS rescore
  9. 2026-07-26 14:54 UTCEPSS rescore
  10. 2026-07-26 03:29 UTCEG score recompute
  11. 2026-07-26 03:29 UTCVendor advisory
  12. 2026-07-26 03:29 UTCGHSA enrichment
  13. 2026-07-25 14:18 UTCEPSS rescore
  14. 2026-07-24 14:17 UTCEPSS rescore
  15. 2026-07-23 14:18 UTCEPSS rescore
  16. 2026-07-23 03:15 UTCEG score recompute
  17. 2026-07-22 22:04 UTCEG score recompute
  18. 2026-07-22 22:04 UTCGHSA enrichment
  19. 2026-07-22 15:34 UTCEG score recompute
  20. 2026-07-22 15:34 UTCGHSA enrichment
  21. 2026-07-22 13:17 UTCEG score recompute
  22. 2026-07-22 13:17 UTCMITRE cvelistV5first tracked

Related CVEs(same vendor + same CWE)

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 82.7% 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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