How severe is CVE-2021-3183?

CVE-2021-3183 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-3183 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3183?

CVE-2021-3183 affects Files Fat Client. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-3183?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-3183 published?

CVE-2021-3183 was published on 2021-01-19 and last updated on 2026-06-17.

CVE-2021-3183

CVE-2021-3183 is a high-severity vulnerability in Files Fat Client with a CVSS 3.x base score of 7.5. 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-613.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-613
Affected product: Files Fat Client
Published: 2021-01-19
Last modified: 2026-06-17

Description

Files.com Fat Client 3.3.6 allows authentication bypass because the client continues to have access after a logout and a removal of a login profile.

Frequently asked questions

What is CVE-2021-3183?: Files.com Fat Client 3.3.6 allows authentication bypass because the client continues to have access after a logout and a removal of a login profile.
How severe is CVE-2021-3183?: CVE-2021-3183 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-3183 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3183?: CVE-2021-3183 affects Files Fat Client. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-3183?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-3183 published?: CVE-2021-3183 was published on 2021-01-19 and last updated on 2026-06-17.

References

https://seclists.org/fulldisclosure/2021/Jan/20

Affected products (1)

cpe:2.3:a:files:fat_client:3.3.6:*:*:*:*:*:*:*

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