CVE-2026-5946
Invalid handling of CLASS != IN
HIGH 7.5
At a glance
- Source
- NVD
- EPSS
- EPSS 1.94 % · percentile 80 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- isc
- NVD status
- Modified
Description
Multiple flaws have been identified in `named` related to the handling of DNS messages whose CLASS is not Internet (`IN`) — for example, `CHAOS` or `HESIOD`, or DNS messages that specify meta-classes (`ANY` or `NONE`) in the question section. Specially crafted requests reaching the affected code paths — recursion, dynamic updates (`UPDATE`), zone change notifications (`NOTIFY`), or processing of `IN`-specific record types in non-`IN` data — can cause assertion failures in `named`. This issue affects BIND 9 versions 9.11.0 through 9.16.50, 9.18.0 through 9.18.48, 9.20.0 through 9.20.22, 9.21.0 through 9.21.21, 9.11.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.48-S1, and 9.20.9-S1 through 9.20.22-S1.
Weaknesses (CWE)
- CWE-20 — Improper Input Validation
- CWE-125 — Out-of-bounds Read
- CWE-617 — Reachable Assertion
- CWE-754 — Improper Check for Unusual or Exceptional Conditions
- CWE-843 — Access of Resource Using Incompatible Type
- CWE-1287 — Improper Validation of Specified Type of Input
References
- https://kb.isc.org/docs/cve-2026-5946
- https://downloads.isc.org/isc/bind9/9.18.49
- https://downloads.isc.org/isc/bind9/9.20.23
- https://downloads.isc.org/isc/bind9/9.21.22
- https://access.redhat.com/security/cve/CVE-2026-5946
- https://bugzilla.redhat.com/show_bug.cgi?id=2479771
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-5946.json
- https://access.redhat.com/errata/RHSA-2026:60383
- https://access.redhat.com/errata/RHSA-2026:62549
- https://access.redhat.com/errata/RHSA-2026:65851
- https://access.redhat.com/errata/RHSA-2026:24338
- https://access.redhat.com/errata/RHSA-2026:24339
- https://access.redhat.com/errata/RHSA-2026:23360
- https://access.redhat.com/errata/RHSA-2026:57189
- https://access.redhat.com/errata/RHSA-2026:55441
- https://access.redhat.com/errata/RHSA-2026:24367
- https://access.redhat.com/errata/RHSA-2026:24368
- https://access.redhat.com/errata/RHSA-2026:20334
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | isc |
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | redhat-SADP |
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD · security-officer@isc.org (Secondary) |
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD · 0b0ca135-0b70-47e7-9f44-1890c2a1c46c (Secondary) |
European references
- ENISA EUVD · EUVD-2026-31107
- GCVE · GCVE-0-2026-5946
CERT-FR advisories
- CERTFR-2026-AVI-0986 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0626 — Multiples vulnérabilités dans ISC BIND · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:*≥ 9.11.0 ≤ 9.16.50cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:*≥ 9.18.0 < 9.18.49cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:*≥ 9.20.0 < 9.20.23cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:*≥ 9.21.0 < 9.21.22
Affected products
| Product | Versions |
|---|---|
| ISC · BIND 9 | affected 9.11.0 ≤ 9.16.50 ; affected 9.18.0 ≤ 9.18.48 ; affected 9.20.0 ≤ 9.20.22 ; affected 9.21.0 ≤ 9.21.21 ; affected 9.11.3-S1 ≤ 9.16.50-S1 ; affected 9.18.11-S1 ≤ 9.18.48-S1 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |