What is CVE-2026-77119?

CVE-2026-77119 is a medium-severity vulnerability in Isc Bind 9, classified under Origin Validation Error. CVSS score: 5.9/10. Published 2026-09-16.

How severe is CVE-2026-77119?

Medium severity. CVSS v3 base score is 5.9 out of 10.

Vulnerability in Isc Bind 9

CVE-2026-77119

A validly signed NSEC3 from an unrelated sibling zone may be accepted as an insecurity proof, downgrading a secure delegation and letting a forged unsigned answer through. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.27-S1.

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N.

Affected products

Isc Bind 9

Weakness classification (CWE)

CWE-346 — Origin Validation Error

References

security-officer@isc.org (vendor-advisory)
security-officer@isc.org (patch)
security-officer@isc.org (patch)

Frequently asked questions

What is CVE-2026-77119?: CVE-2026-77119 is a medium-severity vulnerability in Isc Bind 9, classified under Origin Validation Error. CVSS score: 5.9/10. Published 2026-09-16.
How severe is CVE-2026-77119?: Medium severity. CVSS v3 base score is 5.9 out of 10.