CVE-2023-4809
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.
Scoring
- CVSS base score
- 0.02
- EPSS probability
- 0.47%
- CWE
- CWE-167
- Published
- 2023-09-06
- Last modified
- 2026-03-13
Affected products
- FreeBSD FreeBSD
- FreeBSD FreeBSD
Weakness type
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