Vulnerability intelligence

CVE-2026-3593

A use-after-free vulnerability exists within the DNS-over-HTTPS implementation. This issue affects BIND 9 versions 9.20.0 through 9.20.22, 9.21.0 through 9.21.21, and 9.20.9-S1 through 9.20.22-S1. BIND 9 versions 9.18.0 through 9.18.48 and 9.18.11-S1 through 9.18.48-S1 are NOT affected.

CVSS Score

7.4

High

EPSS — Exploit Probability

1.8%

Riskier than 77% of all CVEs

Exploitation

Not in CISA KEV

No federal exploitation record

Remediation

Patch available

Vendor fix published

NVD entry Vendor patch PoC / advisory

1 article across 1 outlet · first covered May 26, 2026 · latest May 26, 2026

Coverage timeline

BIND 9 flaws let attackers crash DNS and drain bandwidth
securityonline.info · May 26, 2026