CVE•Published 2026-03-25•Modified 2026-05-21•0 articles on news•5 live references•NVD data

CVE-2026-3591Isc · Bind

Vulnerability data via NVD (ingested)

CVSS v3.1

5.4

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

EPSS percentile

Exploit Prediction Scoring System · top 94% of all CVEs

Weaknesses (CWE)

CWE-305Authentication Bypass by Primary Weakness CWE-562Return of Stack Variable Address

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.

Timeline

Published 2026-03-25

Modified 2026-05-21

External references

NVD MITRE Exploit-DB Sploitus VulnCheck

Search for exposed instances

Shodan + Censys queries derived from NVD's CPE data. The vuln tag catches assets Shodan has explicitly linked to this CVE; the product / banner fingerprints find exposed instances even when the vuln tag was never applied (which is common).

Shodan · vuln tag0 hosts

vuln:CVE-2026-3591

Hosts Shodan has explicitly fingerprinted as vulnerable.

Shodan · product

product:"Isc Bind"

All exposed Isc Bind instances — cross-reference with the CVE's affected-version range.

Shodan · banner/body mention

http.html:"Bind"

HTTP body or banner mentions "Bind" — catches deploys Shodan didn't identify as a product.

More intel sources (5)

Shodan report

vuln:CVE-2026-3591