CVE-2026-1519
Excessive NSEC3 iterations cause high CPU load during insecure delegation validation
HIGH 7.5
At a glance
- Source
- NVD
- EPSS
- EPSS 1.69 % · percentile 77 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- isc
- NVD status
- Modified
Description
If a BIND resolver is performing DNSSEC validation and encounters a maliciously crafted zone, the resolver may consume excessive CPU. Authoritative-only servers are generally unaffected, although there are circumstances where authoritative servers may make recursive queries (see: https://kb.isc.org/docs/why-does-my-authoritative-server-make-recursive-queries). This issue affects BIND 9 versions 9.11.0 through 9.16.50, 9.18.0 through 9.18.46, 9.20.0 through 9.20.20, 9.21.0 through 9.21.19, 9.11.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.46-S1, and 9.20.9-S1 through 9.20.20-S1.
Weaknesses (CWE)
References
- https://kb.isc.org/docs/cve-2026-1519
- https://downloads.isc.org/isc/bind9/9.18.47
- https://downloads.isc.org/isc/bind9/9.20.21
- https://downloads.isc.org/isc/bind9/9.21.20
- https://lists.debian.org/debian-lts-announce/2026/04/msg00008.html
- https://access.redhat.com/security/cve/CVE-2026-1519
- https://bugzilla.redhat.com/show_bug.cgi?id=2451305
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-1519.json
- https://access.redhat.com/errata/RHSA-2026:11372
- https://access.redhat.com/errata/RHSA-2026:11371
- https://access.redhat.com/errata/RHSA-2026:34048
- https://access.redhat.com/errata/RHSA-2026:40021
- https://access.redhat.com/errata/RHSA-2026:36610
- https://access.redhat.com/errata/RHSA-2026:43226
- https://access.redhat.com/errata/RHSA-2026:62549
- https://access.redhat.com/errata/RHSA-2026:60019
- https://access.redhat.com/errata/RHSA-2026:65851
- https://access.redhat.com/errata/RHSA-2026:29863
- https://access.redhat.com/errata/RHSA-2026:24851
- https://access.redhat.com/errata/RHSA-2026:8312
- https://access.redhat.com/errata/RHSA-2026:8352
- https://access.redhat.com/errata/RHSA-2026:8155
- https://access.redhat.com/errata/RHSA-2026:16064
- https://access.redhat.com/errata/RHSA-2026:16060
- https://access.redhat.com/errata/RHSA-2026:25171
- https://access.redhat.com/errata/RHSA-2026:15890
- https://access.redhat.com/errata/RHSA-2026:25083
- https://access.redhat.com/errata/RHSA-2026:29110
- https://access.redhat.com/errata/RHSA-2026:25214
- https://access.redhat.com/errata/RHSA-2026:24500
- https://access.redhat.com/errata/RHSA-2026:24934
- https://access.redhat.com/errata/RHSA-2026:8075
- https://access.redhat.com/errata/RHSA-2026:7915
- https://access.redhat.com/errata/RHSA-2026:6935
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-2026-15406
- GCVE · GCVE-0-2026-1519
CERT-FR advisories
- CERTFR-2026-AVI-1376 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0667 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0556 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0386 — Multiples vulnérabilités dans les produits Microsoft · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0360 — 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 < 9.18.47cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:*≥ 9.20.0 < 9.20.21cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:*≥ 9.21.0 < 9.21.20
Affected products
| Product | Versions |
|---|---|
| ISC · BIND 9 | affected 9.11.0 ≤ 9.16.50 ; affected 9.18.0 ≤ 9.18.46 ; affected 9.20.0 ≤ 9.20.20 ; affected 9.21.0 ≤ 9.21.19 ; affected 9.11.3-S1 ≤ 9.16.50-S1 ; affected 9.18.11-S1 ≤ 9.18.46-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 |