High severity · published Dec 13, 2023
CVE-2023-6534
In versions of FreeBSD 14.0-RELEASE before 14-RELEASE-p2, FreeBSD 13.2-RELEASE before 13.2-RELEASE-p7 and FreeBSD 12.4-RELEASE before 12.4-RELEASE-p9, the pf(4) packet filter…
7.5
CVSS
0.7%
EPSS
No
On KEV
Description
In versions of FreeBSD 14.0-RELEASE before 14-RELEASE-p2, FreeBSD 13.2-RELEASE before 13.2-RELEASE-p7 and FreeBSD 12.4-RELEASE before 12.4-RELEASE-p9, the pf(4) packet filter incorrectly validates TCP sequence numbers. This could allow a malicious actor to execute a denial-of-service attack against hosts behind the firewall.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 54% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
Freebsd · Freebsd
12.4; 12.4; 12.4; 12.4; 12.4; 12.4; +17 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-6534
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-6534
Vendor Advisory
https://security.freebsd.org/advisories/FreeBSD-SA-23:17.pf.asc
security.netapp.com
https://security.netapp.com/advisory/ntap-20240112-0007/
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