CVE-2021-21001
CVE-2021-21001 is a critical-severity vulnerability in Wago 750-823 Firmware with a CVSS 3.x base score of 9.1. 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-22.
Key facts
- Severity: Critical (CVSS 3.x base score 9.1)
- CVSS v2: 4.0
- EPSS exploit prediction: 1% (63rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-22
- Affected product: Wago 750-823 Firmware
- Published:
- Last modified:
Description
On WAGO PFC200 devices in different firmware versions with special crafted packets an authorised attacker with network access to the device can access the file system with higher privileges.
Frequently asked questions
- What is CVE-2021-21001?
- On WAGO PFC200 devices in different firmware versions with special crafted packets an authorised attacker with network access to the device can access the file system with higher privileges.
- How severe is CVE-2021-21001?
- CVE-2021-21001 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-21001 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-21001?
- CVE-2021-21001 primarily affects Wago 750-823 Firmware. In total, 27 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-21001?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2021-21001 published?
- CVE-2021-21001 was published on 2021-05-24 and last updated on 2026-06-17.
References
Affected products (27)
- cpe:2.3:o:wago:750-823_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-829_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-831_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-832_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-852_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-862_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-880_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-881_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-882_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-885_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-889_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-890_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-891_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-893_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-8202_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-8203_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-8204_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-8206_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-8207_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-8208_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-8210_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-8211_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-8212_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-8213_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-8214_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-8216_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:wago:750-8217_firmware:*:*:*:*:*:*:*:*
More vulnerabilities in Wago 750-823 Firmware
- CVE-2021-34578 — Critical (CVSS 9.8): This vulnerability allows an attacker who has access to the WBM to read and write settings-parameters of the device by…
- CVE-2021-30193 — Critical (CVSS 9.8): CODESYS V2 Web-Server before 1.1.9.20 has an Out-of-bounds Write.
- CVE-2021-30192 — Critical (CVSS 9.8): CODESYS V2 Web-Server before 1.1.9.20 has an Improperly Implemented Security Check.
- CVE-2021-30190 — Critical (CVSS 9.8): CODESYS V2 Web-Server before 1.1.9.20 has Improper Access Control.
- CVE-2021-30189 — Critical (CVSS 9.8): CODESYS V2 Web-Server before 1.1.9.20 has a Stack-based Buffer Overflow.
- CVE-2021-30188 — Critical (CVSS 9.8): CODESYS V2 runtime system SP before 2.4.7.55 has a Stack-based Buffer Overflow.
All CVEs affecting Wago 750-823 Firmware →
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