How severe is CVE-2021-34594?

CVE-2021-34594 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.

Is CVE-2021-34594 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-34594?

CVE-2021-34594 primarily affects Beckhoff Tf6100 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-34594?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-34594 published?

CVE-2021-34594 was published on 2021-11-04 and last updated on 2026-06-17.

CVE-2021-34594

CVE-2021-34594 is a medium-severity vulnerability in Beckhoff Tf6100 Firmware with a CVSS 3.x base score of 6.5. 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: Medium (CVSS 3.x base score 6.5)
CVSS v2: 8.5
EPSS exploit prediction: 1% (61st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-22
Affected product: Beckhoff Tf6100 Firmware
Published: 2021-11-04
Last modified: 2026-06-17

Description

TwinCAT OPC UA Server in TF6100 and TS6100 in product versions before 4.3.48.0 or with TcOpcUaServer versions below 3.2.0.194 are prone to a relative path traversal that allow administrators to create or delete any files on the system.

Frequently asked questions

What is CVE-2021-34594?: TwinCAT OPC UA Server in TF6100 and TS6100 in product versions before 4.3.48.0 or with TcOpcUaServer versions below 3.2.0.194 are prone to a relative path traversal that allow administrators to create or delete any files on the system.
How severe is CVE-2021-34594?: CVE-2021-34594 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.
Is CVE-2021-34594 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34594?: CVE-2021-34594 primarily affects Beckhoff Tf6100 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-34594?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-34594 published?: CVE-2021-34594 was published on 2021-11-04 and last updated on 2026-06-17.

References

https://cert.vde.com/en/advisories/VDE-2021-051/

Affected products (2)

cpe:2.3:o:beckhoff:tf6100_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:beckhoff:ts6100_firmware:*:*:*:*:*:*:*:*

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