Multiple TCP implementations could allow remote attackers to cause a denial of service (bandwidth and CPU exhaustion) by setting the maximum segment size (MSS) to a very small number and requesting large amounts of data, which generates more packets with less TCP-level data that amplify network traffic and consume more server CPU to process.

References

• https://nvd.nist.gov/vuln/detail/CVE-2001-1244
• https://exchange.xforce.ibmcloud.com/vulnerabilities/6824
• http://www.securityfocus.com/archive/1/195457
• http://www.securityfocus.com/bid/2997