Vulnerability Description
A use-after-free vulnerability exists within the DNS-over-HTTPS implementation. 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 9.18.0 through 9.18.48 and 9.18.11-S1 through 9.18.48-S1 are NOT affected.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Isc | Bind | >= 9.20.0, < 9.20.23 |
Related Weaknesses (CWE)
References
- https://downloads.isc.org/isc/bind9/9.20.23Patch
- https://downloads.isc.org/isc/bind9/9.21.22Patch
- https://kb.isc.org/docs/cve-2026-3593Vendor Advisory
- https://access.redhat.com/errata/RHSA-2026:7412
- https://access.redhat.com/security/cve/CVE-2026-3593
- https://bugzilla.redhat.com/show_bug.cgi?id=2479770
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-3593.json
FAQ
What is CVE-2026-3593?
CVE-2026-3593 is a vulnerability with a CVSS score of 7.4 (HIGH). A use-after-free vulnerability exists within the DNS-over-HTTPS implementation. 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. BIN...
How severe is CVE-2026-3593?
CVE-2026-3593 has been rated HIGH with a CVSS base score of 7.4/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-3593?
Check the references section above for vendor advisories and patch information. Affected products include: Isc Bind.