What is CVE-2026-85522?

CVE-2026-85522 is a medium-severity vulnerability in Valkey-Io Valkey, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 5.3/10. Published 2026-09-04.

How severe is CVE-2026-85522?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Buffer overflow in Valkey-Io Valkey

CVE-2026-85522

A vulnerability was detected in valkey-io valkey up to 9.5.4/9.1.0. Affected by this vulnerability is the function createSlotImportJob of the file src/cluster_migrateslots.c of the component Slot Migration. The manipulation of the argument job_name results in out-of-bounds read. The attack can be executed remotely. The exploit is now public and may be used. Upgrading to version 9.0.5 and 9.1.1 addresses this issue. The patch is identified as f4dc3ca09eb650c2fe14060090a41c524eca803f. Upgrading the affected component is advised.

Vulnerability class: Buffer Overflow

Published 2026-09-04 · last modified 2026-09-08.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

EPSS exploit prediction

EPSS: 0.009 (57.8th percentile), scored 2026-10-20.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 58th percentile — 57.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.009 · change: +0.004

Affected products

Valkey-Io Valkey — versions 9.0, 9.1.0, 9.5.0

Weakness classification (CWE)

References

github.com/valkey-io/valkey/ (product)
github.com/valkey-io/valkey/commit/f4dc3ca09eb650c2fe14060090a41c524eca803f (patch)
github.com/valkey-io/valkey/issues/4207 (issue-tracking, exploit)
github.com/valkey-io/valkey/pull/4210 (issue-tracking, patch)
github.com/valkey-io/valkey/releases/tag/9.1.1 (patch)
vuldb.com/cve/CVE-2026-85522 (third-party-advisory)
vuldb.com/submit/895119 (third-party-advisory)
vuldb.com/vuln/398707 (technical-description, vdb-entry)
vuldb.com/vuln/398707/cti (signature, permissions-required)

Frequently asked questions

What is CVE-2026-85522?: CVE-2026-85522 is a medium-severity vulnerability in Valkey-Io Valkey, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 5.3/10. Published 2026-09-04.
How severe is CVE-2026-85522?: Medium severity. CVSS v3 base score is 5.3 out of 10.