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TI-2025-27502 Aliases CVE-2025-41256GHSA-qq37-7frg-jxx4

Cyberduck and Mountain Duck - Weak Hash Algorithm for Certificate Fingerprint

Priority HIGH 68CWE-328Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
High · High · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

Cyberduck and Mountain Duck improper handle TLS certificate pinning for untrusted certificates (e.g., self-signed), since the certificate fingerprint is stored as SHA-1, although SHA-1 is considered weak. This issue affects Cyberduck: through 9.1.6; Mountain Duck: through 4.17.5.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.0013 2nd percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
iterate GmbHCyberduckup to 9.1.6—No fix listedCNA
iterate GmbHMountain Duckup to 4.17.5—No fix listedCNA
  • Cyberduck Vendoriterate GmbH Affected up to 9.1.6 Fixed in — No fix listed CNA
  • Mountain Duck Vendoriterate GmbH Affected up to 4.17.5 Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-41256
  2. 2026-10-03 Alias added: GHSA-qq37-7frg-jxx4

References

Advisory 2

  • TI-2025-27501 Cyberduck and Mountain Duck - Improper Certificate Store Handling CVSS 3.1HIGH 8.0

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences