CVE-2026-19667

Remote assertion failure via 16-bit length truncation in `dns_ncache_add()`

HIGH
7.5
CVSS Score
Published: September 16, 2026 at 01:46 PM UTC
Updated: September 17, 2026 at 07:16 PM UTC
1 product affected across 1 vendorBIND

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Severity
HIGH7.5
Exploit prediction
EPSS 0.6%
SSVC
No known exploit

Description

If an attacker-controlled authoritative server can produce a negative answer that is exactly 65536 bytes, then a flaw in `named` results in a negative cache entry of 0 bytes. When this entry is subsequently read, `named` aborts. 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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

9.11.0 ≤ v ≤ 9.18.509.11.3-S1 ≤ v ≤ 9.18.50-S19.20.0 ≤ v ≤ 9.20.279.20.9-S1 ≤ v ≤ 9.20.27-S19.21.0 ≤ v ≤ 9.21.259.11.09.11.3-S19.20.09.20.9-S19.21.0

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (3)

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHisc
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusAWAITING ANALYSIS
CWE
CWE-197

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