CVE-2025-14769
NULL Pointer Dereference in FreeBSD tcp-setmss Causes DoS
Publication date: 2026-03-09
Last updated on: 2026-03-17
Assigner: FreeBSD
Description
Description
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| freebsd | freebsd | 13.5 |
| freebsd | freebsd | 13.5 |
| freebsd | freebsd | 13.5 |
| freebsd | freebsd | 13.5 |
| freebsd | freebsd | 13.5 |
| freebsd | freebsd | 13.5 |
| freebsd | freebsd | 13.5 |
| freebsd | freebsd | 13.5 |
| freebsd | freebsd | 14.3 |
| freebsd | freebsd | 14.3 |
| freebsd | freebsd | 14.3 |
| freebsd | freebsd | 14.3 |
| freebsd | freebsd | 14.3 |
| freebsd | freebsd | 14.3 |
| freebsd | freebsd | 14.3 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-476 | The product dereferences a pointer that it expects to be valid but is NULL. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
CVE-2025-14769 is a denial of service (DoS) vulnerability in the FreeBSD ipfw firewall related to the `tcp-setmss` configuration directive.
The `tcp-setmss` handler may free the packet data and return an error without stopping the rule processing engine. This can cause a subsequent firewall rule to allow the now-invalid packet to pass, leading to a NULL pointer dereference and causing a system crash.
This vulnerability is triggered by maliciously crafted packets sent from a remote host when the `tcp-setmss` directive is used.
How can this vulnerability impact me? :
This vulnerability can cause a Denial of Service (DoS) condition on affected FreeBSD systems using the ipfw firewall with the `tcp-setmss` directive.
An attacker can send specially crafted packets remotely that trigger a system crash by causing a NULL pointer dereference in the firewall processing.
Systems not using ipfw with the `tcp-setmss` directive are not impacted.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
There is no specific detection method or commands provided to identify this vulnerability on your network or system.
What immediate steps should I take to mitigate this vulnerability?
To mitigate CVE-2025-14769, you should upgrade to patched versions of FreeBSD stable or release branches dated after November and December 2025.
Apply updates either via binary patches using the freebsd-update utility on supported platforms (amd64, arm64, and i386 on FreeBSD 13) or by applying source code patches from the FreeBSD security website, then recompile the kernel and reboot the system.
If your system does not use ipfw with the tcp-setmss directive, it is not impacted by this vulnerability.