CVE-2020-7451
mediumpriority · track · 21EPSS 0.012 · 67 %ileEUUSEPSS · scored 2026-10-27
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
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (3)
Products and version ranges known to be affected.
- n/a FreeBSD≤ 12.1-STABLE before r358739, 12.1-RELEASE before 12.1-RELEASE-p3, 11.3-STABLE before r358740, 11.3-RELEASE before 11.3-RELEASE-p7enisa_euvdEU
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (6)
External citations — patches, advisories, analysis.
- https://nvd.nist.gov/vuln/detail/CVE-2020-7451cnnvd
- https://security.FreeBSD.org/advisories/FreeBSD-SA-20:04.tcp.asccnnvd
- https://vigilance.fr/vulnerability/FreeBSD-information-disclosure-via-TCP-IPv6-SYN-Cache-31837cnnvd
- https://www.freebsd.org/security/advisories/FreeBSD-SA-20:04.tcp.ascPatchcnnvd
- https://security.FreeBSD.org/advisories/FreeBSD-SA-20:04.tcp.ascenisa_euvd
- https://security.FreeBSD.org/advisories/FreeBSD-SA-20:04.tcp.ascPatchVendor Advisorynvd
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