Unbounded resend loop in BIND 9 resolver
33Vexday Risk Score
No sign of exploitation. It has a public proof of concept.
ssvc Attendcvss 5.3epss 0.7%
from disclosure to weapon25 days
Published on NVDMay 20
1st PoC+25d
exploitation probability
0.7%top 52% of all CVEs
observed exploitation
nono source reports it
1 public exploit(s)
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Affected products
ISC · BIND 9public PoCs found — 1
githubgithub.com/billybaraja/cve-2026-5950-bind9-resolver-dos★ 1⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.