CVE-2021-3772

Related Vulnerabilities: CVE-2021-3772  

A flaw was found in the Linux SCTP stack. A blind attacker may be able to kill an existing SCTP association through invalid chunks if the attacker knows the IP-addresses and port numbers being used and the attacker can send packets with spoofed IP addresses.

Description

A flaw was found in the Linux SCTP stack. A blind attacker may be able to kill an existing SCTP association through invalid chunks if the attacker knows the IP-addresses and port numbers being used and the attacker can send packets with spoofed IP addresses.

Mitigation

As the SCTP module will be auto-loaded when required, its use can be disabled by preventing the module from loading with the following instructions:
if
# echo "install sctp /bin/true" >> /etc/modprobe.d/disable-sctp.conf

The system will need to be restarted if the SCTP modules are loaded. In most circumstances, the SCTP kernel modules will be unable to be unloaded while any network interfaces are active and the protocol is in use.

If the system requires this module to work correctly, this mitigation may not be suitable.

If you need further assistance, see KCS article https://access.redhat.com/solutions/41278 or contact Red Hat Global Support Services.

Additional Information

  • Bugzilla 2000694: CVE-2021-3772 kernel: sctp: Invalid chunks may be used to remotely remove existing associations
  • CWE-354: Improper Validation of Integrity Check Value
  • FAQ: Frequently asked questions about CVE-2021-3772