SB2017021415 - Resource exhaustion in Linux kernel

Description

This security bulletin contains information about 1 security vulnerability.

1) Resource exhaustion (CVE-ID: CVE-2017-5972)

The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.

The TCP stack in the Linux kernel 3.x does not properly implement a SYN cookie protection mechanism for the case of a fast network connection, which allows remote attackers to cause a denial of service (CPU consumption) by sending many TCP SYN packets, as demonstrated by an attack against the kernel-3.10.0 package in CentOS Linux 7. NOTE: third parties have been unable to discern any relationship between the GitHub Engineering finding and the Trigemini.c attack code.

Remediation

Install update from vendor's website.

References

• http://seclists.org/oss-sec/2017/q1/573
• http://www.securityfocus.com/bid/96231
• https://access.redhat.com/security/cve/cve-2017-5972
• https://bugzilla.redhat.com/show_bug.cgi?id=1422081
• https://cxsecurity.com/issue/WLB-2017020112
• https://githubengineering.com/syn-flood-mitigation-with-synsanity/
• https://packetstormsecurity.com/files/141083/CentOS7-Kernel-Denial-Of-Service.html
• https://security-tracker.debian.org/tracker/CVE-2017-5972
• https://www.exploit-db.com/exploits/41350/