cvedb.io
CVE-2026-5947
HIGH · CVSS 7.5
EPSS exploitation probability: 0%
Published 2026-05-20T13:16:40.303 · Last modified 2026-06-30T03:21:10.593

Summary

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 versions 9.18.28 through 9.18.49 and 9.18.28-S1 through 9.18.49-S1 are NOT affected.

Affected products

isc — bind

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.