CVE-2026-32310

Cryptomator: Unverified masterkeyfile key IDs can access arbitrary local or UNC paths

Published Mar 20, 2026 CVSS 3.1 · 4.1 Medium EPSS < 1% KEV · Not listed
Description
Cryptomator encrypts data being stored on cloud infrastructure. From version 1.6.0 to before version 1.19.1, vault configuration is parsed before its integrity is verified, and the masterkeyfile loader uses the unverified keyId as a filesystem path. The loader resolves keyId.getSchemeSpecificPart() directly against the vault path and immediately calls Files.exists(...). This allows a malicious vault config to supply parent-directory escapes, absolute local paths, or UNC paths (e.g., masterkeyfile://attacker/share/masterkey.cryptomator). On Windows, the UNC variant is especially dangerous because Path.resolve("//attacker/share/...") becomes \\attacker\share\..., so the existence check can trigger outbound SMB access before the user even enters a passphrase. This issue has been patched in version 1.19.1.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Microsoft
Microsoft windows
CPEs cpe:2.3:a:cryptomator:cryptomator:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows:*:*:*:*:*:*:*:*
Vendors & Products Microsoft
Microsoft windows
Type Values Removed Values Added
First Time appeared Cryptomator
Cryptomator cryptomator
Vendors & Products Cryptomator
Cryptomator cryptomator
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Cryptomator encrypts data being stored on cloud infrastructure. From version 1.6.0 to before version 1.19.1, vault configuration is parsed before its integrity is verified, and the masterkeyfile loader uses the unverified keyId as a filesystem path. The loader resolves keyId.getSchemeSpecificPart() directly against the vault path and immediately calls Files.exists(...). This allows a malicious vault config to supply parent-directory escapes, absolute local paths, or UNC paths (e.g., masterkeyfile://attacker/share/masterkey.cryptomator). On Windows, the UNC variant is especially dangerous because Path.resolve("//attacker/share/...") becomes \\attacker\share\..., so the existence check can trigger outbound SMB access before the user even enters a passphrase. This issue has been patched in version 1.19.1.
Title Cryptomator: Unverified masterkeyfile key IDs can access arbitrary local or UNC paths
Weaknesses CWE-22
References
Metrics cvssV3_1

{'score': 4.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:N/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Mar 20, 2026, 7:56 PM
Reserved
Mar 11, 2026, 9:16 PM
Status
Analyzed
Published
Mar 20, 2026, 7:16 PM
Modified
Jun 17, 2026, 10:35 AM