CVE-2023-33011

Name of the Vulnerable Software and Affected Versions Zyxel ATP series versions 5.10 through 5.36 Patch 2 Zyxel USG FLEX series versions 5.00 through 5.36 Patch 2 Zyxel USG FLEX 50(W) series versions 5.10 through 5.36 Patch 2 Zyxel USG20(W)-VPN series versions 5.10 through 5.36 Patch 2 Zyxel VPN series versions 5.00 through 5.36 Patch 2

Description A format string vulnerability in the Zyxel firmware could allow an unauthenticated, LAN-based attacker to execute some OS commands by using a crafted PPPoE configuration on an affected device when the cloud management mode is enabled. The vulnerability is related to the use of uncontrolled format strings, which may allow a remote attacker to execute arbitrary commands.

Recommendations For Zyxel ATP series versions 5.10 through 5.36 Patch 2, update to a version later than 5.36 Patch 2. For Zyxel USG FLEX series versions 5.00 through 5.36 Patch 2, update to a version later than 5.36 Patch 2. For Zyxel USG FLEX 50(W) series versions 5.10 through 5.36 Patch 2, update to a version later than 5.36 Patch 2. For Zyxel USG20(W)-VPN series versions 5.10 through 5.36 Patch 2, update to a version later than 5.36 Patch 2. For Zyxel VPN series versions 5.00 through 5.36 Patch 2, update to a version later than 5.36 Patch 2. As a temporary workaround, consider disabling the cloud management mode until a patch is available. Restrict access to the PPPoE configuration to minimize the risk of exploitation.