# CVE-2026-5947

> Undefined behavior may result due to a race condition leading to a use-after-free violation. If BIND receives an incoming DNS message signed with SIG(0), it begins work to validate that signature. If, during that validation, the "recursive-clients" limit is reached (as would occur during a query flood), and that same DNS message is discarded per the limit, there is a brief window of time while the SIG(0) validation may attempt to read the now-discarded DNS message. 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 versio

- **CVSS:** 7.5 (HIGH)
- **EPSS:** 0.0%
- **CWE:** CWE-362, CWE-416

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-5947
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