CVE-2021-34570
Phoenix Contact: DoS for PLCnext Control devices in versions prior to 2021.0.5 LTS
HIGH
7.5
CVSS Score
Published: September 27, 2021 at 08:25 AM UTC
Updated: June 17, 2026 at 03:56 AM UTC
12 products affected across 1 vendorAxc F 2152 FirmwareAxc F 2152 Starterkit FirmwareRfc 4072S Firmware
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Severity
HIGH7.5
Exploit prediction
EPSS 1.0%
Description
Multiple Phoenix Contact PLCnext control devices in versions prior to 2021.0.5 LTS are prone to a DoS attack through special crafted JSON requests.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
v < 2021.0.5
Affected range stops below 2021.0.5, so it looks safe — our inference, not a vendor statement
phoenixcontact-axc-f-1152 (same device)
v < 2021.0.5
Affected range stops below 2021.0.5, so it looks safe — our inference, not a vendor statement
phoenixcontact-axc-f-2152 (same device)
v < 2021.0.5
Affected range stops below 2021.0.5, so it looks safe — our inference, not a vendor statement
phoenixcontact-axc-f-2152-starterkit (same device)
v < 2021.0.5
Affected range stops below 2021.0.5, so it looks safe — our inference, not a vendor statement
phoenixcontact-axc-f-3152 (same device)
v < 2021.0.5
Affected range stops below 2021.0.5, so it looks safe — our inference, not a vendor statement
phoenixcontact-plcnext-technology-starterkit (same device)
v < 2021.0.5
Affected range stops below 2021.0.5, so it looks safe — our inference, not a vendor statement
phoenixcontact-rfc-4072s (same device)
80%
All versions
80%
All versions
All versions
80%
All versions
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
References (1)
x_refsource_CONFIRMPatchThird Party Advisory
Source: [email protected]
https://cert.vde.com/en/advisories/VDE-2021-029/CVSS
7.5HIGHCERTVDE
- Attack Vector
- NETWORK
- Complexity
- LOW
- Privileges
- NONE
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality
- NONE
- Integrity
- NONE
- Availability
- HIGH
Vector?
Quick Info
StatusMODIFIED
CWE
CWE-20
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