CVE-2023-6534 - CVE House
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Status published Unknown CVE-2023-6534

TCP spoofing vulnerability in pf(4)

Vulnerability Description

In versions of FreeBSD 14.0-RELEASE before 14-RELEASE-p2, FreeBSD 13.2-RELEASE before 13.2-RELEASE-p7 and FreeBSD 12.4-RELEASE before 12.4-RELEASE-p9, the pf(4) packet filter incorrectly validates TCP sequence numbers.  This could allow a malicious actor to execute a denial-of-service attack against hosts behind the firewall.

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:

  • Yuxiang Yang, Ao Wang, Xuewei Feng, Qi Li and Ke Xu from Tsinghua University

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Affected Vendor

Affected Software

FreeBSD
Vulnerable Versions:
14.0-RELEASE, 13.2-RELEASE, 12.4-RELEASE

Timeline

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

CVSS Vectors

No vector data available

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.