CVE-2026-3591
A stack use-after-return flaw in SIG(0) handling code may enable ACL bypass
MEDIUM 5.4
At a glance
- Source
- NVD
- EPSS
- EPSS 0.37 % · percentile 30 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- isc
- NVD status
- Analyzed
Description
A use-after-return vulnerability exists in the `named` server when handling DNS queries signed with SIG(0). Using a specially-crafted DNS request, an attacker may be able to cause an ACL to improperly (mis)match an IP address. In a default-allow ACL (denying only specific IP addresses), this may lead to unauthorized access. Default-deny ACLs should fail-secure. This issue affects BIND 9 versions 9.20.0 through 9.20.20, 9.21.0 through 9.21.19, and 9.20.9-S1 through 9.20.20-S1. BIND 9 versions 9.18.0 through 9.18.46 and 9.18.11-S1 through 9.18.46-S1 are NOT affected.
Weaknesses (CWE)
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | MEDIUM 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N | isc |
| CVSS 3.1 | MEDIUM 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N | NVD · security-officer@isc.org (Secondary) |
European references
- ENISA EUVD · EUVD-2026-15413
- GCVE · GCVE-0-2026-3591
CERT-FR advisories
- 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:*:*:*:*:-:*:*:*≥ 9.20.0 < 9.20.21cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:*≥ 9.21.0 < 9.21.20
Affected products
| Product | Versions |
|---|---|
| ISC · BIND 9 | affected 9.20.0 ≤ 9.20.20 ; affected 9.21.0 ≤ 9.21.19 ; affected 9.20.9-S1 ≤ 9.20.20-S1 ; unaffected 9.18.0 ≤ 9.18.46 ; unaffected 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 |