Is CVE-2026-21863 actively exploited?

No active exploitation of CVE-2026-21863 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2026-21863 be exploited remotely?

Yes. CVE-2026-21863 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2026-21863?

CVE-2026-21863 has a CVSS score of 7.5 (HIGH) and an EPSS exploitation probability of 0.01%.

HOME VULNERABILITIESCVE-2026-21863

HIGH

CVE-2026-21863

CWE-125Published: February 23, 2026· Updated: Feb 25, 2026

7.5

CVSS v3.1

EPSS:0.01%probability of exploitation in 30 daysPercentile:2.9th

Official Description

Valkey is a distributed key-value database. Prior to versions 9.0.2, 8.1.6, 8.0.7, and 7.2.12, a malicious actor with access to the Valkey clusterbus port can send an invalid packet that may cause an out bound read, which might result in the system crashing. The Valkey clusterbus packet processing code does not validate that a clusterbus ping extension packet is located within buffer of the clusterbus packet before attempting to read it. Versions 9.0.2, 8.1.6, 8.0.7, and 7.2.12 fix the issue. As an additional mitigation, don't expose the cluster bus connection directly to end users, and protect the connection with its own network ACLs.

NVD Source

Technical Analysis

CVE-2026-21863 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in availability disruption (denial of service), with a CVSS base score of 7.5.