CVE-2026-5950mediumCWE-606

CVE-2026-5950: medium-severity vulnerability in ISC BIND 9

Unbounded resend loop in BIND 9 resolver

Published

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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
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 9
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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