CVE-2026-77119
NSEC3 insecure-referral proof can use unrelated cached NSEC3 RRsets
CVSS Score
5.9
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-346 |
| Vendor | isc |
| Product | bind 9 |
| Published | Sep 16, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
None
Affected Versions
ISC / BIND 9
9.11.0 ≤ 9.18.50 9.20.0 ≤ 9.20.27 9.21.0 ≤ 9.21.25 9.11.3-S1 ≤ 9.18.50-S1 9.20.9-S1 ≤ 9.20.27-S1