Security readout for executives and security teams
Plain-English summary
CVE-2021-4406 is a critical OSNEXUS QuantaStor issue where an authenticated user can abuse alert/webhook handling to run commands as root. That can turn a compromised or malicious privileged account into full appliance control. Public sources do not prove active exploitation, but they include proof-of-concept detail.
Executive priority
Treat this as urgent for any QuantaStor deployment because successful exploitation means root-level appliance compromise. Prioritize environments with shared administrator access, exposed management interfaces, or unreviewed alert/webhook configurations. Business urgency is high, but verify applicability because public version data is incomplete.
Technical view
The CVE describes authenticated root remote command execution through alert creation and ITSM webhook handling in QuantaStor. The weakness is classified as CWE-77 command injection. The record has CVSS 3.1 score 9.1 with network access, low complexity, high privileges required, no user interaction, and full confidentiality, integrity, and availability impact.
Likely exposure
Exposure is likely limited to OSNEXUS QuantaStor environments where authenticated users can access alert or ITSM webhook management. The title mentions version 6.0.0.355 and others, but the provided affected-version data is incomplete, so all QuantaStor deployments should be checked against vendor guidance.
Exploitation context
The source bundle says proof-of-concept information is public, but it does not cite active exploitation. The CVE is not marked as CISA KEV in the provided data. Exploitation requires authenticated high-privilege access, which reduces broad internet risk but increases insider and post-compromise risk.
Researcher notes
The strongest evidence is the CVE/DIVD description of authenticated command injection leading to root execution. Avoid assuming unauthenticated exposure or confirmed exploitation. The affected-version field in the supplied data is ambiguous, so version validation depends on vendor or advisory clarification.
Mitigation direction
- Check OSNEXUS guidance for affected and fixed QuantaStor versions.
- Patch or upgrade QuantaStor according to vendor instructions.
- Restrict QuantaStor management access to trusted networks and administrators.
- Limit alert and ITSM webhook management permissions.
- Review privileged accounts and remove unnecessary access.
- Monitor vendor and DIVD advisories for updated remediation details.
Validation and detection
- Inventory all QuantaStor deployments and record installed versions.
- Confirm whether alert manager and ITSM webhook features are enabled.
- Review who has permissions to create or modify alerts.
- Audit recent alert, webhook, and test-alert changes.
- Check appliance logs for unexpected privileged command execution indicators.
- Compare findings against OSNEXUS and DIVD advisory updates.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-77: Command execution behavior lookup
Command injection weaknesses can lead defenders to review execution techniques and command interpreter telemetry. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCredential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-4406 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H2.36Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
9.1CriticalVector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://csirt.divd.nl/DIVD-2021-00020/CVE reference · third-party-advisory
- https://www.osnexus.com/products/software-defined-storageCVE reference · product
- https://csirt.divd.nl/CVE-2021-4406CVE reference · third-party-advisory, exploit
- https://www.divd.nl/DIVD-2021-00020CVE reference · third-party-advisory, x_transferred
- https://csirt.divd.nl/cves/CVE-2021-4406/CVE reference · exploit
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Neutralization of Special Elements used in a Command ('Command Injection')
Improper Neutralization of Special Elements used in a Command ('Command Injection') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.