How severe is CVE-2018-20684?

CVE-2018-20684 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 none, integrity high, and availability none.

Is CVE-2018-20684 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-20684?

CVE-2018-20684 affects Winscp. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-20684?

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-2018-20684 published?

CVE-2018-20684 was published on 2019-01-10 and last updated on 2026-06-17.

CVE-2018-20684

CVE-2018-20684 is a high-severity vulnerability in Winscp 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 6.4
EPSS exploit prediction: 3% (85th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Winscp
Published: 2019-01-10
Last modified: 2026-06-17

Description

In WinSCP before 5.14 beta, due to missing validation, the scp implementation would accept arbitrary files sent by the server, potentially overwriting unrelated files. This affects TSCPFileSystem::SCPSink in core/ScpFileSystem.cpp.

Frequently asked questions

What is CVE-2018-20684?: In WinSCP before 5.14 beta, due to missing validation, the scp implementation would accept arbitrary files sent by the server, potentially overwriting unrelated files. This affects TSCPFileSystem::SCPSink in core/ScpFileSystem.cpp.
How severe is CVE-2018-20684?: CVE-2018-20684 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 none, integrity high, and availability none.
Is CVE-2018-20684 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-20684?: CVE-2018-20684 affects Winscp. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-20684?: 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-2018-20684 published?: CVE-2018-20684 was published on 2019-01-10 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:winscp:winscp:*:*:*:*:*:*:*:*

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