CVE-2023-4236 - CVE House
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Status published High CVE-2023-4236

named may terminate unexpectedly under high DNS-over-TLS query load

Vulnerability Description

A flaw in the networking code handling DNS-over-TLS queries may cause `named` to terminate unexpectedly due to an assertion failure. This happens when internal data structures are incorrectly reused under significant DNS-over-TLS query load. This issue affects BIND 9 versions 9.18.0 through 9.18.18 and 9.18.11-S1 through 9.18.18-S1.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • ISC would like to thank Robert Story from the USC/ISI DNS root server operations team for bringing this vulnerability to our attention.

References

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Affected Vendor

Affected Software

BIND 9
Vulnerable Versions:
9.18.0, 9.18.11-S1

Timeline

Official Publish: September 20th, 2023
Last Modified: February 13th, 2025
Added to House: July 22nd, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.