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CWE WEAKNESSES  /  CWE-420

CWE-420

Unprotected Alternate Channel

Base

What it is

The product protects a primary channel, but it does not use the same level of protection for an alternate channel.

Impact

Access ControlGain Privileges or Assume Identity, Bypass Protection Mechanism

Mitigations

  • [Architecture and Design] Identify all alternate channels and use the same protection mechanisms that are used for the primary channels.

Real-world CVE examples

  • CVE-2020-8004 — When the internal flash is protected by blocking access on the Data Bus (DBUS), it can still be indirectly accessed through the Instruction Bus (IBUS).
  • CVE-2002-0567 — DB server assumes that local clients have performed authentication, allowing attacker to directly connect to a process to load libraries and execute commands; a
  • CVE-2002-1578 — Product does not restrict access to underlying database, so attacker can bypass restrictions by directly querying the database.
  • CVE-2003-1035 — User can avoid lockouts by using an API instead of the GUI to conduct brute force password guessing.
  • CVE-2002-1863 — FTP service can not be disabled even when other access controls would require it.
  • CVE-2002-0066 — Windows named pipe created without authentication/access control, allowing configuration modification.
  • CVE-2004-1461 — Router management interface spawns a separate TCP connection after authentication, allowing hijacking by attacker coming from the same IP address.

Related weaknesses

Test & detect

Browse all common weaknesses, check related exploited CVEs, or map to ATT&CK techniques.

Source: MITRE CWE. View on cwe.mitre.org →

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