CVE-2021-35621

Exploitation likely. EPSS gives it a 50% chance of exploitation in the next 30 days. A vendor fix is available.

CVSS 3.16.3Medium EPSS percentile99th50% chance in 30 days CISA KEVNot listedNo confirmed exploitation
No public exploit known FixVendor fixNo build named by the sources

Published 2021-10-20Updated 2024-11-21Sources: CVE.org, NVD

NVD CVE.org

What to do

The vendor has published a fix. Version details are below where the sources state them.

Oracle Corporation MySQL ClusterAffected: 7.4.33 and priorUpgrade to: not statedAffected: 7.5.23 and priorUpgrade to: not statedAffected: 7.6.19 and priorUpgrade to: not statedAffected: 8.0.26 and priorUpgrade to: not statedStated by: CVE record

Versions as the sources state them. Full version matrix after sign-in

Steps

Written by AI from the record

Check whether you run MySQL Cluster and identify its installed version.
If it is 7.4.33 or earlier, 7.5.23 or earlier, 7.6.19 or earlier, or 8.0.26 or earlier, review Oracle's October 2021 security advisory for the applicable update.
Schedule the vendor-provided MySQL Cluster update after testing it in a non-production environment.
Restrict access to the network segment used by the cluster to authorized administrators and systems only.

Vendor advisory Some work to apply

Check it yourselfA free OpenVAS check exists for this CVE. Run it against your hosts.Is your organisation exposed?Request an assessment to establish which checks fit your systems.

What it is

From the CVE record

Vulnerability in the MySQL Cluster product of Oracle MySQL (component: Cluster: General). Supported versions that are affected are 7.4.33 and prior, 7.5.23 and prior, 7.6.19 and prior and 8.0.26 and prior. Difficult to exploit vulnerability allows high privileged attacker with access to the physical communication segment attached to the hardware where the MySQL Cluster executes to compromise MySQL Cluster. Successful attacks require human interaction from a person other than the attacker. Successful attacks of this vulnerability can result in takeover of MySQL Cluster. CVSS 3.1 Base Score 6.3 (Confidentiality, Integrity and Availability impacts). CVSS Vector: (CVSS:3.1/AV:A/AC:H/PR:H/UI:R/S:U/C:H/I:H/A:H).

In plain language

Written by AI from the record

MySQL Cluster versions 7.4.33 and earlier, 7.5.23 and earlier, 7.6.19 and earlier, and 8.0.26 and earlier have a flaw, but a typical small business is unlikely to face immediate risk.

A difficult-to-exploit MySQL Cluster vulnerability requires a highly privileged attacker on the attached physical network segment and interaction by another person, potentially resulting in full cluster compromise.

If you're affected

Full cluster takeover
Database data exposure
Database data changes
Service disruption

What is it

This is a weakness in MySQL Cluster that could let an insider with unusually close access take control of the database cluster. It is like someone who already has staff-only building access finding a way to take over the building’s control room after another person helps open the wrong door.

Who is affected

This matters to you if you run MySQL Cluster, especially for important databases or services. It is only a risk when an attacker already has high-level access to the physical network connected to the cluster and another person interacts with them.

How urgent is it

This is green because there are no known public exploits and it is not listed as actively exploited by CISA. Plan the update and access review, but this does not indicate an emergency for most small businesses.

What to do — in detail

Confirm whether any MySQL Cluster nodes are deployed and record each node’s version and network placement. The affected branches are 7.4 through 7.4.33, 7.5 through 7.5.23, 7.6 through 7.6.19, and 8.0 through 8.0.26; the supplied findings do not identify exact fixed version numbers, so select the applicable vendor-supported update from Oracle’s October 2021 advisory before changing production systems.

Test the chosen update against the cluster’s application dependencies and follow the normal rolling-maintenance procedure where supported. If patching must wait, limit the cluster communication segment to required hosts and administrators, review privileged access, and investigate unexpected access attempts or configuration changes on cluster nodes. There is no CISA KEV remediation due date because this CVE is not listed in KEV.

Technical context

CVSS v3.1 score: 6.3 (Medium), with AV:A/AC:H/PR:H/UI:R/S:U/C:H/I:H/A:H. The weakness type is not specified. Exploitation requires adjacent physical-network access, high privileges, high complexity, and user interaction; successful exploitation can affect confidentiality, integrity, and availability. CISA KEV does not list this CVE, and no public exploit code is on record. EPSS predicts a 50.0% likelihood and is rising (99th percentile), but this is predictive rather than evidence of active exploitation.

This is a general assessment based on public vulnerability data. It does not account for your specific infrastructure — when in doubt, consult a security specialist.

Exploitation

Where each signal puts this CVE on the scale from published to confirmed exploited.

EPSS99th

CISA KEV

Not in the catalog. CISA has not confirmed exploitation.

Public exploits

No public exploit or proof of concept found in the sources we track.

EPSS

50% chance of exploitation activity in the next 30 days, which ranks it in the 99th percentile of scored CVEs.

Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.

Lifecycle

8 events over 1790 days, from the signal feeds we watch.

2026-09-14EPSS band changemoderate → highepss band change
2026-06-25OpenVAS check added
2026-06-22EPSS band changelow → moderate
2024-11-21Patch availablerecord updated
2021-10-20Publishedweakness classified

Affected products

netappcommercial · US
Oracle Corporationcommercial · USaka oracle, oracle corp.
- MySQL ClusterDatabaseOn-premDatabases / relational

And 1 more affected product. See all after sign-in

Technical detail

CVSS 3.1 vector

Open in the CVSS calculator

CVSS:3.1/AV:A/AC:H/PR:H/UI:R/S:U/C:H/I:H/A:H

Scored 6.3 by NVD.

How it is reached

Attack Vector AdjacentRequires access to the local network (e.g. same Wi-Fi, Bluetooth)
Attack Complexity HighRequires specific conditions like a race condition or non-default configuration
Privileges Required HighRequires admin or elevated privileges
User Interaction RequiredA user must click a link, open a file, or perform some action

Scope

Scope UnchangedImpact is limited to the vulnerable component itself

Impact if exploited

Confidentiality HighTotal information disclosure — all data in the component is compromised
Integrity HighTotal loss of integrity — attacker can modify any data in the component
Availability HighTotal denial of service — the component is completely unavailable

Weaknesses

NVD-CWE-noinfoNo name in the record

Sources

References in the record

Watch the software you run.

My Stack ranks new CVEs for your products by real-world exploitation, so the next serious one reaches you without reading every advisory.

We'll flag the next CVE, public exploit or patch for Netapp, not every advisory.

A free account adds

The full version matrix and every affected product
Exploit links, proofs of concept and Metasploit modules
Email alerts for the products you watch
The same data over REST API, MCP and CLI

Create a free account