CVE-2026-86227
A weakness has been identified in valkey-io valkey up to 9.0.5/9.1.1. This affects the function kvstoreGetHashtable of the file src/kvstore.c. This manipulation of the argument didx causes out-of-bounds read. It is possible to initiate the attack remotely. The attack is considered to have high complexity. It is indicated that the exploitability is difficult. The exploit has been made available to the public and could be used for attacks. Patch name: 4691888e7fab3df128f0bde5750c9fde2ae552fa. To fix this issue, it is recommended to deploy a patch. Exploitation requires cluster mode plus attacker-controlled dump.rdb at startup (data-dir write access, replication feed, or a stored crafted RDB) - an attacker-position DoS at boot, not network pre-auth. The issue report was closed stating it "is worth fixing for the sake of memory safety… but I don't think it meets our bar for a security disclosure."
What this means for your business
- An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.3% chance of attack attempts being seen in the next 30 days, ranking above 25% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 3.1 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L- CVSS v4
- 1.3
- Weakness
- CWE-119
- Assigned by
- cna@vuldb.com
Dates
- Published
- 2026-09-06
- Last modified
- 2026-09-09
- Sources
- NVD
References
- https://github.com/user-attachments/files/30195539/RDB.zip
- https://github.com/valkey-io/valkey/
- https://github.com/valkey-io/valkey/commit/4691888e7fab3df128f0bde5750c9fde2ae552fa
- https://github.com/valkey-io/valkey/issues/4222
- https://github.com/valkey-io/valkey/pull/4229
- https://vuldb.com/cve/CVE-2026-86227
- https://vuldb.com/submit/897659
- https://vuldb.com/vuln/399380
- https://vuldb.com/vuln/399380/cti