CVE-2021-33537
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedIn Weidmueller Industrial WLAN devices in multiple versions an exploitable remote code execution vulnerability exists in the iw_webs configuration parsing functionality. A specially crafted user name entry can cause an overflow of an error message buffer, resulting in remote code execution. An attacker can send commands while authenticated as a low privilege user to trigger this vulnerability.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceWeidmueller Industrial WLAN devices contain a buffer overflow vulnerability in the iw_webs configuration parsing functionality. Specifically, a specially crafted user name entry overflows an error message buffer, allowing an authenticated low-privilege attacker to achieve remote code execution.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data<= 1.16.18<= 1.11.10<= 1.16.18<= 1.11.10<= 1.16.18<= 1.11.10<= 1.16.18<= 1.11.10<= 1.16.18<= 1.11.10<= 1.16.18<= 1.11.10<= 1.16.18<= 1.11.10<= 1.16.18<= 1.11.10CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
-
Identify the Weidmueller device modelLocate the device label or access the web management interface to confirm the exact model number (e.g., Ie Wl Bl Ap Cl Eu, Ie Wlt Bl Ap Cl Us, etc.)Affected if The device is one of the Weidmueller Industrial WLAN models listed in the affected products
-
Determine the installed firmware versionLog into the device web interface and navigate to the firmware or status page to view the current firmware version, or use the device's command-line interface if availableAffected if The firmware version is 1.16.18 or lower, or 1.11.10 or lower (the device falls within either of these two version ranges)
-
Verify the iw_webs web interface is accessibleAttempt to access the device web management interface via HTTP/HTTPS on the default management port (typically 80 or 443)Affected if The web interface responds and is accessible on the network
-
Confirm authentication is enabled on the web interfaceCheck if the web login page is present and requires credentials, or verify in the device security settings that authentication is configured for the web interfaceAffected if Web-based management is enabled with authentication configured, allowing an attacker to authenticate and trigger the vulnerable code path
A user is affected if they have a Weidmueller Industrial WLAN device (any of the listed models) running firmware version 1.16.18 or lower, or version 1.11.10 or lower, with the web management interface (iw_webs) accessible and authentication enabled.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scopedApply vendor-supplied firmware updates to address the vulnerability. Additionally, restrict network access to the device management interface to reduce attack surface.
Firmware version > 1.16.18 or > 1.11.10 (contact Weidmueller for exact fixed release)
- Check the current firmware version of the Weidmueller Industrial WLAN device by accessing the web interface or using the device's management interface
- Navigate to the Weidmueller support portal or official website to obtain the latest firmware version
- Download the firmware update that addresses CVE-2021-33537 (firmware versions higher than 1.16.18 or 1.11.10)
- Review the firmware release notes to confirm the security fix for CVE-2021-33537 is included
- Back up the current device configuration before performing the upgrade
- Upload and install the new firmware through the device's web interface or management tool
- After rebooting, verify the new firmware version is installed and the device is functioning normally
- Confirm the vulnerability is addressed by reviewing the security release notes or changelog
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation4.0 h
- Implementation2.0 h
- Testing4.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,392.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-33537 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-33537 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data