SB2019053021 - Denial of service in ISC Bind

Description

This security bulletin contains information about 1 vulnerability.

1) Input validation error (CVE-ID: CVE-2019-6469)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: 8.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to improper input validation in the EDNS Client Subnet (ECS) feature for recursive resolvers when processing a response with malformed RRSIGs. A remote attacker can cause a server to perform a query whose answer is accompanied by malformed RRSIGs to cause a denial of service.

Only servers using the recursive ECS feature are vulnerable.

Remediation

Install update from vendor's website.

References

• https://kb.isc.org/docs/cve-2019-6469
• https://kb.isc.org/docs/cve-2019-6465