CVEvulnerability
CVE-2023-4809
7.5 HIGH
Official page ↗
- Status
- Modified
- Published
- 2023-09-06
- Last modified
- 2026-06-17
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 7.5 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- Weaknesses
- CWE-167
Description
In pf packet processing with a 'scrub fragment reassemble' rule, a packet containing multiple IPv6 fragment headers would be reassembled, and then immediately processed. That is, a packet with multiple fragment extension headers would not be recognized as the correct ultimate payload. Instead a packet with multiple IPv6 fragment headers would unexpectedly be interpreted as a fragmented packet, rather than as whatever the real payload is.
As a result, IPv6 fragments may bypass pf firewall rules written on the assumption all fragments have been reassembled and, as a result, be forwarded or processed by the host.
Affected configurations
• freebsd freebsd (< 12.4)
• freebsd freebsd (>= 13.0 < 13.2)
• freebsd freebsd 12.4
• freebsd freebsd 13.2
Related
Weakness · CWE (1)
- CWE-167 Improper Handling of Additional Special Element weakness
References
- http://www.openwall.com/lists/oss-security/2023/09/08/5 Mailing List, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2023/09/08/6 Mailing List, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2023/09/08/7 Mailing List, Third Party Advisory
- https://security.FreeBSD.org/advisories/FreeBSD-SA-23:10.pf.asc Vendor Advisory
- https://security.netapp.com/advisory/ntap-20231221-0009/ security.netapp.com
- http://www.openwall.com/lists/oss-security/2023/09/08/5 Mailing List, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2023/09/08/6 Mailing List, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2023/09/08/7 Mailing List, Third Party Advisory
- https://security.FreeBSD.org/advisories/FreeBSD-SA-23:10.pf.asc Vendor Advisory
- https://security.netapp.com/advisory/ntap-20231221-0009/ security.netapp.com