CVE-2021-47244 mptcp: Fix out of bounds when parsing TCP options

2024-05-2114:19:42

Linux

www.cve.org

mptcp

tcp options

linux kernel

vulnerability

out of bounds

parsing

6.5 Medium

AI Score

Confidence

High

0.0004 Low

EPSS

Percentile

15.6%

JSON

In the Linux kernel, the following vulnerability has been resolved:

mptcp: Fix out of bounds when parsing TCP options

The TCP 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.

This fix is inspired by commit 9609dad263f8 (“ipv4: tcp_input: fix stack
out of bounds when parsing TCP options.”).

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "net/mptcp/options.c"
    ],
    "versions": [
      {
        "version": "cec37a6e41aa",
        "lessThan": "73eeba71dc99",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "cec37a6e41aa",
        "lessThan": "76e02b8905d0",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "cec37a6e41aa",
        "lessThan": "07718be26568",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "net/mptcp/options.c"
    ],
    "versions": [
      {
        "version": "5.6",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "5.6",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.10.46",
        "lessThanOrEqual": "5.10.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.12.13",
        "lessThanOrEqual": "5.12.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.13",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]