ipfw denial of service
FreeBSD-SA-25:11.ipfw · CVE-2025-14769
Our decision for FreeSense
FreeBSD corrected this on 2025-11-04, before the FreeBSD source pin of every FreeSense version.
- Advisory: corrected 2025-11-04
- FreeSense 1.0 pin: e004ff15f87e (2026-08-03)
- FreeSense 1.1 pin: a52c50b4b7c2 (2026-10-04)
- FreeSense 1.2 pin: a52c50b4b7c2 (2026-10-04)
By FreeSense version
| Version | Status | FreeBSD pin |
|---|---|---|
| FreeSense 1.01.0.7 · frozen, no further fixes | FixedFreeBSD pin of 2026-08-03 | 2026-08-03e004ff15 |
| FreeSense 1.11.1.9 | FixedFreeBSD pin of 2026-10-04 | 2026-10-04a52c50b4 |
| FreeSense 1.21.2.0-DEVELOPMENT | FixedFreeBSD pin of 2026-10-04 | 2026-10-04a52c50b4 |
Workaround
No workaround is available, but systems that do not use ipfw(4) with the `tcp-setmss` directive are not affected.
What FreeBSD says
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.
Impact
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.
Excerpt from the FreeBSD advisory. Read the original for the full text and the fix.