How severe is CVE-2021-33537?

CVE-2021-33537 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-33537 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33537?

CVE-2021-33537 primarily affects Weidmueller Ie-wl-bl-ap-cl-eu Firmware. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-33537?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-33537 published?

CVE-2021-33537 was published on 2021-06-25 and last updated on 2026-06-17.

CVE-2021-33537

CVE-2021-33537 is a high-severity vulnerability in Weidmueller Ie-wl-bl-ap-cl-eu Firmware with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-120.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Weidmueller Ie-wl-bl-ap-cl-eu Firmware
Published: 2021-06-25
Last modified: 2026-06-17

Description

In 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.

Frequently asked questions

What is CVE-2021-33537?: In 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.
How severe is CVE-2021-33537?: CVE-2021-33537 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-33537 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33537?: CVE-2021-33537 primarily affects Weidmueller Ie-wl-bl-ap-cl-eu Firmware. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-33537?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-33537 published?: CVE-2021-33537 was published on 2021-06-25 and last updated on 2026-06-17.

References

https://cert.vde.com/en-us/advisories/vde-2021-026

Affected products (8)

cpe:2.3:o:weidmueller:ie-wl-bl-ap-cl-eu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:weidmueller:ie-wlt-bl-ap-cl-eu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:weidmueller:ie-wl-bl-ap-cl-us_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:weidmueller:ie-wlt-bl-ap-cl-us_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:weidmueller:ie-wl-vl-ap-br-cl-eu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:weidmueller:ie-wlt-vl-ap-br-cl-eu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:weidmueller:ie-wl-vl-ap-br-cl-us_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:weidmueller:ie-wlt-vl-ap-br-cl-us_firmware:*:*:*:*:*:*:*:*

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