CVE-2023-4809
7.5 · HIGHOverview
CVE-2023-4809 is a high-severity vulnerability affecting freebsd freebsd. It was published on September 6, 2023 and has a CVSS 3.1 base score of 7.5 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from freebsd. Update freebsd to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| freebsd | freebsd | >= 0, < 12.4 | Affected |
References
Frequently Asked Questions
What is CVE-2023-4809?
CVE-2023-4809 is a high-severity vulnerability affecting freebsd freebsd. It was published on September 6, 2023 and has a CVSS 3.1 base score of 7.5 (HIGH).
How severe is CVE-2023-4809?
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2023-4809?
Check the references section for vendor advisories and patches from freebsd. Update freebsd to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2023-4809?
CyberStrike's AI-powered security agents can automatically detect CVE-2023-4809 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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