CVE-2023-53543: vdpa: Add max vqp attr to vdpa_nl_policy for nlattr length check

Vulnerability summary

CVE-2023-53543 is a high (CVSS 7.8) Out-of-bounds Write vulnerability in linux. EPSS estimates a 0.17% chance of exploitation in the next 30 days, higher than 6.2% of scored vulnerabilities.

Timeline

1. 04-10-2025
   PublishedVulnerability first disclosed.
2. 01-06-2026
   Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: vdpa: Add max vqp attr to vdpa_nl_policy for nlattr length check The vdpa_nl_policy structure is used to validate the nlattr when parsing the incoming nlmsg. It will ensure the attribute being described produces a valid nlattr pointer in info->attrs before entering into each handler in vdpa_nl_ops. That is to say, the missing part in vdpa_nl_policy may lead to illegal nlattr after parsing, which could lead to OOB read just like CVE-2023-3773. This patch adds the missing nla_policy for vdpa max vqp attr to avoid such bugs.

• CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.