dbcve.org
FreeBSDOperating system

CVE-2025-14769

HIGH · 7.5 CVSS v3.1 Published 2026-03-09
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

In the tcp-setmss handler, when packet data is freed due to an error condition, the rule processing engine continues executing instead of halting. A subsequent rule can then allow the now-freed traffic, causing a NULL pointer dereference when the system attempts to access the deallocated packet data. This leads to a denial of service condition when maliciously crafted packets are processed.

MitigationReview all rulesets using the tcp-setmss directive and ensure proper error handling configurations are in place. Consider upgrading to the latest version when a patch becomes available, or implement additional rule validation to prevent the vulnerable code path from being exercised.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
FreeBSDOperating system
Affected:= 13.5= 14.3

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check FreeBSD version
    Run 'freebsd-version -u' or 'uname -r' to get the installed FreeBSD version
    Affected if Version is 13.5 or 14.3 (exact match to affected versions)
  2. Verify ipfw firewall is active
    Run 'ipfw list' or check if ipfw is enabled via 'service ipfw status'
    Affected if ipfw is loaded and processing rules
  3. Identify tcp-setmss rules in active configuration
    Run 'ipfw show | grep setmss' or inspect the active ruleset for 'tcp-setmss' directive usage
    Affected if Any rule containing the tcp-setmss directive is present in the active ruleset
  4. Check for error-handling rules after tcp-setmss
    Review the ipfw ruleset order and look for allow/pass rules that follow tcp-setmss rules which could be reached if packet data is freed prematurely
    Affected if There are allow rules positioned after tcp-setmss rules that could process the freed packet context

You are affected if running FreeBSD 13.5 or 14.3 with ipfw enabled and tcp-setmss rules present in your active firewall configuration.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Review all rulesets using the tcp-setmss directive and ensure proper error handling configurations are in place. Consider upgrading to the latest version when a patch becomes available, or implement additional rule validation to prevent the vulnerable code path from being exercised.

Recommended fix Moderate confidence

FreeBSD 14.3 or later stable release

  1. 1. Update your FreeBSD system to the latest security-patched release using 'freebsd-update fetch install' or by upgrading to the latest stable branch
  2. 2. If immediate patching is not possible, review pf rulesets to minimize the use of the 'tcp-setmss' directive in combination with rules that may pass traffic
  3. 3. Consider implementing additional network-level filtering as a temporary mitigation
  4. 4. After patching, verify the tcp-setmss functionality works correctly with your firewall rules
Caveat Standard FreeBSD upgrade considerations apply - review /usr/UPDATING and ensure all packages are compatible

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in FreeBSD Scoped from the published advisory
  • Consultation4.0 h
  • Implementation12.0 h
  • Testing8.0 h
  • Review / QA4.0 h
28.0 hours of engineering $4,880
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $7,808.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2025-14769 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-14769 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data