CVE-2021-33535 | WEIDMUELLER: WLAN devices affected by exploitable format string vulnerability

In Weidmueller Industrial WLAN devices in multiple versions an exploitable format string vulnerability exists in the iw_console conio_writestr functionality. A specially crafted time server entry can cause an overflow of the time server buffer, resulting in remote code execution. An attacker can send commands while authenticated as a low privilege user to trigger this vulnerability.

Published: 2021-06-25 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-33535 is rated Moderate Risk (58.8/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.91%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-33535

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-03-30 7.88% 1.91% -5.97%
2 2025-03-29 1.91% 7.88% +5.97%
3 2025-03-19 — 1.91% —

Full EPSS history (10 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-33535

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 5.9 [email protected]
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 5.9 [email protected]
6.5 2.0 MEDIUM
AV:N/AC:L/Au:S/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.0 6.4 [email protected]

Weakness enumeration for CVE-2021-33535

Affected software / configurations for CVE-2021-33535

Vendor Product Version Raw CPE
weidmueller ie-wl-bl-ap-cl-eu_firmware <= 1.16.18 cpe:2.3:o:weidmueller:ie-wl-bl-ap-cl-eu_firmware:*:*:*:*:*:*:*:*
weidmueller ie-wlt-bl-ap-cl-eu_firmware <= 1.16.18 cpe:2.3:o:weidmueller:ie-wlt-bl-ap-cl-eu_firmware:*:*:*:*:*:*:*:*
weidmueller ie-wl-bl-ap-cl-us_firmware <= 1.16.18 cpe:2.3:o:weidmueller:ie-wl-bl-ap-cl-us_firmware:*:*:*:*:*:*:*:*
weidmueller ie-wlt-bl-ap-cl-us_firmware <= 1.16.18 cpe:2.3:o:weidmueller:ie-wlt-bl-ap-cl-us_firmware:*:*:*:*:*:*:*:*
weidmueller ie-wl-vl-ap-br-cl-eu_firmware <= 1.16.18 cpe:2.3:o:weidmueller:ie-wl-vl-ap-br-cl-eu_firmware:*:*:*:*:*:*:*:*
weidmueller ie-wlt-vl-ap-br-cl-eu_firmware <= 1.16.18 cpe:2.3:o:weidmueller:ie-wlt-vl-ap-br-cl-eu_firmware:*:*:*:*:*:*:*:*
weidmueller ie-wl-vl-ap-br-cl-us_firmware <= 1.16.18 cpe:2.3:o:weidmueller:ie-wl-vl-ap-br-cl-us_firmware:*:*:*:*:*:*:*:*
weidmueller ie-wlt-vl-ap-br-cl-us_firmware <= 1.16.18 cpe:2.3:o:weidmueller:ie-wlt-vl-ap-br-cl-us_firmware:*:*:*:*:*:*:*:*
weidmueller ie-wl-bl-ap-cl-eu_firmware <= 1.11.10 cpe:2.3:o:weidmueller:ie-wl-bl-ap-cl-eu_firmware:*:*:*:*:*:*:*:*
weidmueller ie-wlt-bl-ap-cl-eu_firmware <= 1.11.10 cpe:2.3:o:weidmueller:ie-wlt-bl-ap-cl-eu_firmware:*:*:*:*:*:*:*:*
weidmueller ie-wl-bl-ap-cl-us_firmware <= 1.11.10 cpe:2.3:o:weidmueller:ie-wl-bl-ap-cl-us_firmware:*:*:*:*:*:*:*:*
weidmueller ie-wlt-bl-ap-cl-us_firmware <= 1.11.10 cpe:2.3:o:weidmueller:ie-wlt-bl-ap-cl-us_firmware:*:*:*:*:*:*:*:*
weidmueller ie-wl-vl-ap-br-cl-eu_firmware <= 1.11.10 cpe:2.3:o:weidmueller:ie-wl-vl-ap-br-cl-eu_firmware:*:*:*:*:*:*:*:*
weidmueller ie-wlt-vl-ap-br-cl-eu_firmware <= 1.11.10 cpe:2.3:o:weidmueller:ie-wlt-vl-ap-br-cl-eu_firmware:*:*:*:*:*:*:*:*
weidmueller ie-wl-vl-ap-br-cl-us_firmware <= 1.11.10 cpe:2.3:o:weidmueller:ie-wl-vl-ap-br-cl-us_firmware:*:*:*:*:*:*:*:*
weidmueller ie-wlt-vl-ap-br-cl-us_firmware <= 1.11.10 cpe:2.3:o:weidmueller:ie-wlt-vl-ap-br-cl-us_firmware:*:*:*:*:*:*:*:*

References for CVE-2021-33535

cvelogic Threat Intelligence