CVE-2026-19667
HIGHCVE-2026-19667 is a high-severity (CVSS 7.5) CWE-197 vulnerability. O3 Security confirms whether CVE-2026-19667 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
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…
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.
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of the affected component has shipped for CVE-2026-19667 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-19667 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-19667. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-19667 in your dependencies?
O3 detects CVE-2026-19667 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.