CVE-2020-4420: 
IBM Db2 vulnerability analysis and mitigation

IBM DB2 for Linux, UNIX and Windows (includes DB2 Connect Server) versions 9.7, 10.1, 10.5, 11.1, and 11.5 contained a vulnerability (CVE-2020-4420) that could allow an unauthenticated attacker to cause a denial of service due to a hang in the execution of a terminate command. The vulnerability was discovered and assigned on December 30, 2019 (CVE MITRE).

The vulnerability has been assigned a CVSS Base score of 7.5 with a vector of CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. This indicates that the vulnerability can be exploited remotely with low attack complexity, requires no privileges or user interaction, and can result in high availability impact while not affecting confidentiality or integrity (IBM Support).

If successfully exploited, this vulnerability could allow an unauthenticated attacker to cause a denial of service condition in the IBM DB2 database system by triggering a hang in the execution of a terminate command. This could result in system unavailability, affecting database operations (IBM Support).

The vulnerability can be exploited by an unauthenticated attacker remotely, requiring low attack complexity and no user interaction. The attack vector is network-accessible (IBM Support).

IBM has released special builds containing interim fixes for all affected versions. The fixes are available based on the most recent fixpack level for each impacted release: V9.7 FP11, V10.1 FP6, V10.5 FP11, 11.1 FP5, and V11.5 GA. These can be applied to any affected fixpack level of the appropriate release to remediate this vulnerability. No workarounds are available (IBM Support).