CVE-2023-4809

Summary

CVECVE-2023-4809
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2023-09-06 20:15:00 UTC
Updated2023-09-12 15:50:00 UTC
DescriptionIn 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.

Risk And Classification

Problem Types: NVD-CWE-Other

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Operating System Freebsd Freebsd All All All All
Operating System Freebsd Freebsd 12.4 - All All
Operating System Freebsd Freebsd 12.4 p1 All All
Operating System Freebsd Freebsd 12.4 p2 All All
Operating System Freebsd Freebsd 12.4 p3 All All
Operating System Freebsd Freebsd 12.4 p4 All All
Operating System Freebsd Freebsd 12.4 rc2-p1 All All
Operating System Freebsd Freebsd 12.4 rc2-p2 All All
Operating System Freebsd Freebsd 13.2 - All All
Operating System Freebsd Freebsd 13.2 p1 All All
Operating System Freebsd Freebsd 13.2 p2 All All

References

ReferenceSourceLinkTags
oss-security - CVE-2023-4809: FreeBSD pf bypass when using IPv6 MISC www.openwall.com
security.FreeBSD.org/advisories/FreeBSD-SA-23:10.pf.asc MISC security.FreeBSD.org
oss-security - Re: CVE-2023-4809: FreeBSD pf bypass when using IPv6 MISC www.openwall.com
oss-security - Re: CVE-2023-4809: FreeBSD pf bypass when using IPv6 MISC www.openwall.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis
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