How severe is CVE-2026-21863?

CVE-2026-21863 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-21863 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-21863?

CVE-2026-21863 affects Lfprojects Valkey. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-21863?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-21863 have an EU (EUVD) identifier?

Yes. CVE-2026-21863 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-7513.

When was CVE-2026-21863 published?

CVE-2026-21863 was published on 2026-02-23 and last updated on 2026-06-30.

CVE-2026-21863

CVE-2026-21863 is a high-severity vulnerability in Lfprojects Valkey with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-125.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (42nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-7513
Weakness: CWE-125
Affected product: Lfprojects Valkey
Published: 2026-02-23
Last modified: 2026-06-30

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.

Frequently asked questions

What is CVE-2026-21863?: 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.
How severe is CVE-2026-21863?: CVE-2026-21863 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-21863 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-21863?: CVE-2026-21863 affects Lfprojects Valkey. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-21863?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-21863 have an EU (EUVD) identifier?: Yes. CVE-2026-21863 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-7513.
When was CVE-2026-21863 published?: CVE-2026-21863 was published on 2026-02-23 and last updated on 2026-06-30.

References

Affected products (1)

cpe:2.3:a:lfprojects:valkey:*:*:*:*:*:*:*:*

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