SECUFOCUSNOW
Home›CVE index›CVE-2026-1519
Review reviewHigh

CVE-2026-1519

ISC BIND 9, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 10.0 Extended Update Support

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.

CVSS
7.5
EPSS
1.60%
73.4% percentile
CISA KEV
Not listed
Published
2026.03.25
PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability1.60%
Technical severityCVSS 7.5

Vulnerability overview

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.

Affected product and versions

Product
ISC BIND 9, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 10.0 Extended Update Support
Affected versions
>= 9.11.0 <= 9.16.50, >= 9.18.0 <= 9.18.46, >= 9.20.0 <= 9.20.20, >= 9.21.0 <= 9.21.19, >= 9.11.3-S1 <= 9.16.50-S1, >= 9.18.11-S1 <= 9.18.46-S1, >= 9.20.9-S1 <= 9.20.20-S1, >= 9.18.0 < 9.18.47, >= 9.20.0 < 9.20.21, >= 9.21.0 < 9.21.20
Fixed versions
9.18.47, 9.20.21, 9.21.20

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that ISC BIND 9, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 10.0 Extended Update Support and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
CWE-606, CWE-770