Security readout for executives and security teams
Plain-English summary
Certain Weidmuller industrial WLAN devices contain a command injection flaw that could let a low-privileged authenticated user remotely control the device. For sites using these devices in operational networks, the business risk is loss of confidentiality, integrity, and availability for network infrastructure.
Executive priority
Treat this as high priority for OT or industrial environments using the affected devices. The issue requires credentials, but low privilege is enough, and compromise of WLAN infrastructure can disrupt operations or enable further access.
Technical view
CVE-2021-33533 is a CWE-78 OS command injection in Weidmuller iw_webs functionality. User-controlled input in the iw_serverip parameter can be reflected into a later iw_system call. The CVSS 3.1 score is 8.8 with network access, low privileges, no user interaction, and high CIA impact.
Likely exposure
Exposure is limited to the listed Weidmuller IE-WL(T)-BL-AP-CL-XX and IE-WL(T)-VL-AP-CL-XX industrial WLAN devices and specific part-number variants. The bundle provides no CPEs, firmware ranges, internet exposure data, or deployment prevalence.
Exploitation context
The source states an attacker must be authenticated as a low-privilege user. The flaw is remotely reachable over the network and does not require user interaction. The bundle does not cite active exploitation, public exploit availability, or KEV listing.
Researcher notes
Evidence is source-limited: CVE metadata and the VDE advisory reference identify affected models and command injection mechanics, but the bundle does not include fixed versions, patch names, exploit telemetry, or detailed detection guidance.
Mitigation direction
- Check VDE-2021-026 and Weidmuller support for fixed firmware or official mitigations.
- Restrict affected device management access to trusted administrative networks only.
- Remove unused low-privilege accounts and rotate shared device credentials.
- Monitor affected devices for unexpected configuration or operational changes.
- Prioritize remediation where devices support industrial or production networks.
Validation and detection
- Inventory Weidmuller industrial WLAN devices and match exact model and part numbers.
- Compare device firmware and configuration status against VDE-2021-026 guidance.
- Confirm management interfaces are not reachable from untrusted networks.
- Review available logs or change history for suspicious authenticated activity.
- Document compensating controls where vendor fixes are unavailable or unconfirmed.
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-78: 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 lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-33533 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
- High
- CVSS
- 8.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/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:L/UI:N/S:U/C:H/I:H/A:H2.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
8.8HighVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://cert.vde.com/en-us/advisories/vde-2021-026CVE reference · x_refsource_CONFIRM
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 an OS Command ('OS Command Injection')
Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.