Valkey clusterCreatePublishMsgBlock Numeric Truncation Error Remote Code Execution Vulnerability

October 28th, 2026
ZDI-26-833 ZDI-CAN-28318

CVE ID

CVSS Score

8.8 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected Vendors

Valkey

Affected Products

Valkey

Vulnerability Details

This vulnerability allows remote attackers to execute arbitrary code on affected installations of Valkey. Authentication is required to exploit this vulnerability.

The specific flaw exists within the handling of the parameters supplied to the PUBLISH message handler. The issue results from the lack of proper validation of user-supplied data, which can result in an incorrect calculation before allocating a buffer. An attacker can leverage this vulnerability to execute code in the context of the service account.

Additional Details

Valkey has issued an update to correct this vulnerability. More details can be found at:
https://github.com/valkey-io/valkey/security/advisories/GHSA-f4q9-j22m-xqq9

Disclosure Timeline

  • 2026-10-01 - Vulnerability reported to vendor
  • 2026-10-28 - Coordinated public release of advisory
  • 2026-10-28 - Advisory Updated

Credit

Nenad Stojanovski

Back to Advisories