CVE-2026-5950

Name
CVE-2026-5950
Description
An unbounded resend loop vulnerability exists in the BIND 9 resolver state machine during bad-server handling, enabling a remote unauthenticated attacker to cause severe resource exhaustion by sending queries that trigger specific retry conditions. This issue affects BIND 9 versions 9.18.36 through 9.18.48, 9.20.8 through 9.20.22, 9.21.7 through 9.21.21, 9.18.36-S1 through 9.18.48-S1, and 9.20.9-S1 through 9.20.22-S1.
NVD Severity
unknown
Other trackers
CVE, NVD, CERT, CVE Details, CIRCL, Arch Linux, Debian, Red Hat, Ubuntu, Gentoo, SUSE (Bugzilla), SUSE (CVE), Mageia
Mailing lists
oss-security, full-disclosure, bugtraq
Exploits
Exploit DB, Metasploit
Forges
GitHub (code, issues), Aports (code, issues)

References

Type URI
security-officer@isc.org https://downloads.isc.org/isc/bind9/9.18.49
security-officer@isc.org https://downloads.isc.org/isc/bind9/9.20.23
security-officer@isc.org https://downloads.isc.org/isc/bind9/9.21.22
security-officer@isc.org https://kb.isc.org/docs/cve-2026-5950

Match rules

CPE URI Source package Min version Max version
cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:* bind >= 9.18.36 < 9.18.49
cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:* bind >= 9.20.8 < 9.20.23
cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:* bind >= 9.21.7 < 9.21.21

Vulnerable and fixed packages

Source package Branch Version Maintainer Status
bind edge-main 9.20.23-r0 Mike Crute <mike@crute.us> fixed
bind edge-main 9.20.22-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind edge-main 9.20.21-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind edge-main 9.20.20-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind edge-main 9.20.19-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind edge-main 9.20.18-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind edge-main 9.20.17-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind edge-main 9.20.16-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind edge-main 9.20.15-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind edge-main 9.20.13-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind edge-main 9.20.12-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind edge-main 9.20.11-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind edge-main 9.20.10-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind edge-main 9.20.9-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind edge-main 9.20.8-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.23-main 9.20.23-r0 Mike Crute <mike@crute.us> fixed
bind 3.23-main 9.20.22-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.23-main 9.20.21-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.23-main 9.20.20-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.23-main 9.20.19-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.23-main 9.20.18-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.23-main 9.20.17-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.22-main 9.20.23-r0 Mike Crute <mike@crute.us> fixed
bind 3.22-main 9.20.22-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.22-main 9.20.21-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.22-main 9.20.18-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.22-main 9.20.17-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.22-main 9.20.16-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.22-main 9.20.15-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.22-main 9.20.13-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.22-main 9.20.12-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.22-main 9.20.11-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.22-main 9.20.10-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.22-main 9.20.9-r0 None possibly vulnerable
bind 3.21-main 9.18.49-r0 Mike Crute <mike@crute.us> fixed
bind 3.21-main 9.18.47-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.21-main 9.18.44-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.21-main 9.18.41-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.21-main 9.18.39-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.21-main 9.18.37-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.21-main 9.18.36-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.20-main 9.18.49-r0 Mike Crute <mike@crute.us> fixed
bind 3.20-main 9.18.47-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.20-main 9.18.44-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.20-main 9.18.41-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.20-main 9.18.39-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.20-main 9.18.37-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.20-main 9.18.36-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.19-main 9.18.44-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.19-main 9.18.41-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.19-main 9.18.39-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.19-main 9.18.37-r0 Mike Crute <mike@crute.us> possibly vulnerable
bind 3.19-main 9.18.36-r0 Mike Crute <mike@crute.us> possibly vulnerable