How severe is CVE-2021-37594?

CVE-2021-37594 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-37594 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-37594?

CVE-2021-37594 affects Freerdp. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-37594?

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-2021-37594 published?

CVE-2021-37594 was published on 2021-07-30 and last updated on 2026-06-17.

CVE-2021-37594

CVE-2021-37594 is a critical-severity vulnerability in Freerdp with a CVSS 3.x base score of 9.8. 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-20.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 1% (69th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Freerdp
Published: 2021-07-30
Last modified: 2026-06-17

Description

In FreeRDP before 2.4.0 on Windows, wf_cliprdr_server_file_contents_request in client/Windows/wf_cliprdr.c has missing input checks for a FILECONTENTS_SIZE File Contents Request PDU.

Frequently asked questions

What is CVE-2021-37594?: In FreeRDP before 2.4.0 on Windows, wf_cliprdr_server_file_contents_request in client/Windows/wf_cliprdr.c has missing input checks for a FILECONTENTS_SIZE File Contents Request PDU.
How severe is CVE-2021-37594?: CVE-2021-37594 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-37594 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-37594?: CVE-2021-37594 affects Freerdp. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-37594?: 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-2021-37594 published?: CVE-2021-37594 was published on 2021-07-30 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*

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