FreeBSD Pf tcp-setmss Null Deref DoS via Rule Engine Bypass
CVE-2025-14769 Published on March 9, 2026
ipfw denial of service
In some cases, the `tcp-setmss` handler may free the packet data and throw an error without halting the rule processing engine. A subsequent rule can then allow the traffic after the packet data is gone, resulting in a NULL pointer dereference.
Maliciously crafted packets sent from a remote host may result in a Denial of Service (DoS) if the `tcp-setmss` directive is used and a subsequent rule would allow the traffic to pass.
Vulnerability Analysis
CVE-2025-14769 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity, and a high impact on availability.
Weakness Type
NULL Pointer Dereference
A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. NULL pointer dereference issues can occur through a number of flaws, including race conditions, and simple programming omissions.
Products Associated with CVE-2025-14769
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Affected Versions
FreeBSD:- Version 14.3-RELEASE and below p7 is affected.
- Version 13.5-RELEASE and below p8 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.