CVE-2026-3593
Medium
Elevated severity or exploit probability.
CVSS base
7.4
HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H
EPSS — probability of exploitation (30 days)
1.5%
73.7th percentile
CISA KEV
Not listed
Weakness / dates
CWE-825
Published 2026-05-20 · modified 2026-08-24
CVSS breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H
| Attack Vector | N | Network |
| Attack Complexity | H | High |
| Privileges Required | N | None |
| User Interaction | N | None |
| Scope | U | Unchanged |
| Confidentiality | H | High |
| Integrity | N | None |
| Availability | H | High |
Timeline
- 2026-05-20 — Published (NVD)
- 2026-08-24 — Last modified (NVD)
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.
Affected
References
- 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://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