CVE-2021-47244
kernel: mptcp: Fix out of bounds when parsing TCP options
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · May 21, 2024
Updated · February 2, 2026
Description
A vulnerability was found in the Linux kernel's mptcp implementation, where theTCP option parser in mptcp (mptcp_get_options) could read one byte out of bounds. When the length is 1, the execution flow gets into the loop, reads one byte of the opcode, and if the opcode is neither TCPOPT_EOL nor TCPOPT_NOP, it reads one more byte, which exceeds the length of 1.
Statement
None of the products shipped by Red Hat are affected by this vulnerability.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update the affected package as soon as possible.
CVSS / CWE
CVSS 3.1 · 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE-125 · Out-of-bounds Read