CVE-2026-81563

HIGHPre-NVD 7.57.5—
EchelonGraph scoreHIGH confidence

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-09-16. a secondary CVSS source baseline 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
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: 0%CVSS: 7.5Exploit: None knownExposed: 0

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

A BIND resolver encountering an SVCB/HTTPS AliasMode record referencing 14 or more SVCB/HTTPS ServiceMode records may fail to properly deallocate internal resources. If this happens repeatedly, resource exhaustion will eventually prevent the resolver from performing new recursive lookups. This issue affects BIND 9 versions 9.18.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.18.11-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.27-S1.

CVSS v3
7.5
EG Score
7.5(high)
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%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
41%
KEV
Not listed

Published

September 16, 2026

Last Modified

September 17, 2026

Advisory Details (3)

Auto-updated Sep 16, 2026
No patch confirmed yet.
generic

CVE-2026-81563: SVCB AliasMode additional-data error leaks qpcache references

https://kb.isc.org/docs/cve-2026-81563
generic

Index of /isc/bind9/9.21.26

https://downloads.isc.org/isc/bind9/9.21.26
generic

Index of /isc/bind9/9.20.29

https://downloads.isc.org/isc/bind9/9.20.29

Vendor Advisories for CVE-2026-81563(1)

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 20× in last 7d / 20× 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. 2026-09-20 14:00 UTCGHSA enrichment
  2. 2026-09-20 02:45 UTCEG score recompute
  3. 2026-09-20 02:45 UTCGHSA enrichment
  4. 2026-09-19 15:30 UTCGHSA enrichment
  5. 2026-09-19 04:12 UTCEG score recompute
  6. 2026-09-19 04:12 UTCGHSA enrichment
  7. 2026-09-18 19:28 UTCEPSS rescore
  8. 2026-09-18 16:57 UTCGHSA enrichment
  9. 2026-09-18 05:42 UTCEG score recompute
  10. 2026-09-18 05:42 UTCGHSA enrichment
  11. 2026-09-17 18:26 UTCEG score recompute
  12. 2026-09-17 18:26 UTCGHSA enrichment
  13. 2026-09-17 18:00 UTCEG score recompute
  14. 2026-09-17 18:00 UTCGHSA enrichment
  15. 2026-09-17 06:48 UTCGHSA enrichment
  16. 2026-09-16 19:32 UTCEG score recompute
  17. 2026-09-16 19:32 UTCGHSA enrichment
  18. 2026-09-16 14:23 UTCEG score recompute
  19. 2026-09-16 14:06 UTCEG score recompute
  20. 2026-09-16 14:05 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-81563?
CVE-2026-81563 is a high vulnerability published on September 16, 2026. A BIND resolver encountering an SVCB/HTTPS AliasMode record referencing 14 or more SVCB/HTTPS ServiceMode records may fail to properly deallocate internal resources. If this happens repeatedly, resource exhaustion will eventually prevent the resolver from performing new recursive lookups. This…
When was CVE-2026-81563 disclosed?
CVE-2026-81563 was first published in the National Vulnerability Database on September 16, 2026, with the most recent update on September 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-81563 actively exploited?
CVE-2026-81563 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 59.4% of all scored CVEs.
What is the CVSS score of CVE-2026-81563?
CVE-2026-81563 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-81563?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-81563, 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-2026-81563

Explore →

Is Your Infrastructure Affected by CVE-2026-81563?

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

Start Free Scan →Browse All CVEs