Medium severity · published Apr 28, 2020
CVE-2020-7451
In FreeBSD 12.1-STABLE before r358739, 12.1-RELEASE before 12.1-RELEASE-p3, 11.3-STABLE before r358740, and 11.3-RELEASE before 11.3-RELEASE-p7, a TCP SYN-ACK or challenge TCP-ACK…
5.3
CVSS
1.2%
EPSS
No
On KEV
Description
In FreeBSD 12.1-STABLE before r358739, 12.1-RELEASE before 12.1-RELEASE-p3, 11.3-STABLE before r358740, and 11.3-RELEASE before 11.3-RELEASE-p7, a TCP SYN-ACK or challenge TCP-ACK segment over IPv6 that is transmitted or retransmitted does not properly initialize the Traffic Class field disclosing one byte of kernel memory over the network.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.2% · higher than 67% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
Freebsd · Freebsd
11.3; 11.3; 11.3; 11.3; 11.3; 11.3; +4 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-7451
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-7451
Patch
https://security.FreeBSD.org/advisories/FreeBSD-SA-20:04.tcp.asc
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