CVE-2026-3593
Published: May 21, 2026Last modified: May 27, 2026
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.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 9.8 |
| Attack Vector | NETWORK |
| Attack complexity | LOW |
| Privileges required | NONE |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | HIGH |
| Integrity impact | HIGH |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | bind | Fixed (9.18.49-r0) |
| 25 LTS | bind | Fixed (9.20.23-r0) | |
| Stream | bind | Fixed (9.20.23-r0) |
References
- 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://downloads.isc.org/isc/bind9/9.20.23
- https://downloads.isc.org/isc/bind9/9.21.22
- https://kb.isc.org/docs/cve-2026-3593
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-3593.json