Use After Free in Valkey-Io Valkey

CVE-2026-63639

Valkey is a distributed key-value database. Prior to 7.2.14, 8.0.10, 8.1.9, 9.0.5, and 9.1.1, Valkey's RESTORE command accepts a malformed RDB stream payload that assigns one Pending Entry List NACK to multiple consumers during stream consumer-group deserialization, causing a use-after-free when one consumer is deleted while another still references the shared NACK and potentially allowing remote code execution. This issue is fixed in versions 7.2.14, 8.0.10, 8.1.9, 9.0.5, and 9.1.1.

Vulnerability class: Use-After-Free

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-63639?
CVE-2026-63639 is a high-severity vulnerability in Valkey-Io Valkey, classified under Use After Free. CVSS score: 8.8/10. Published 2026-08-18.
How severe is CVE-2026-63639?
High severity. CVSS v3 base score is 8.8 out of 10.