SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2025-41255

Cyberduck and Mountain Duck improperly handle TLS certificate pinning for untrusted certificates (e.g., self-signed), unnecessarily installing it to the Windows Certificate Store of the current user without any restrictions.

HIGH 8.0EPSS 0.19%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.19%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Cyberduck and Mountain Duck improperly handle TLS certificate pinning for untrusted certificates (e.g., self-signed), unnecessarily installing it to the Windows Certificate Store of the current user without any restrictions. This issue affects Cyberduck through 9.1.6 and Mountain Duck through 4.17.5.

CVSS 3.1
8.0 HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N
EPSS
0.19% probability · 8th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-266
Source
1e3a9e0f-5156-4bf8-b8a3-cc311bfc0f4a
EPSS trend
0%3%5%27 October 2026: 0.19%27 October 202627 October 2026

EPSS 0.2% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.