QID 15154

QID 15154: ISC BIND Extreme CPU consumption Vulnerability (CVE-2023-50387)

ISC BIND (Berkley Internet Domain Name) is an implementation of DNS protocols.

Affected versions:
BIND 9.0.0 - 9.16.46
BIND 9.18.0 - 9.18.22
BIND 9.19.0 - 9.19.20
BIND Supported Preview Edition 9.9.3-S1 - 9.16.46-S1
BIND Supported Preview Edition 9.18.11-S1 - 9.18.22-S1

Patched Versions:
BIND 9.16.48
BIND 9.18.24
BIND 9.19.21
BIND Supported Preview Edition 9.16.48-S1
BIND Supported Preview Edition 9.18.24-S1

QID Detection Logic:
This unauthenticated check detects vulnerable systems by fetching the version information from the BIND service using banner.

By flooding the target resolver with queries exploiting this flaw an attacker can significantly impair the resolver's performance, effectively denying legitimate clients access to the DNS resolution service.

  • CVSS V3 rated as High - 7.5 severity.
  • CVSS V2 rated as High - 7.8 severity.
  • Solution
    Customers are advised to upgrade to the patched version latest release of CVE-2023-50387.
    Workaround:
    Workaround:
    Although this is not recommended, disabling DNSSEC validation entirely will remove the vulnerability. We instead strongly advise installing one of the versions of BIND listed below, in which an exceptionally complex DNSSEC validation will no longer impede other server workload.

    Vendor References

    CVEs related to QID 15154

    Software Advisories
    Advisory ID Software Component Link
    CVE-2023-50867 URL Logo kb.isc.org/docs/cve-2023-50867