CVE-2026-33472CWE-305CWE-319

Cryptomator Hub OAuth token exchange HTTP downgrade via getAuthority() scheme confusion (CVE-2026-32303 bypass)

Medium · published April 16, 2026

CVSS v3.1
4.8
EPSS
0%
Percentile
3.1
In the wild
Unconfirmed
What it is

Cryptomator is an open-source client-side encryption application for cloud storage. Version 1.19.1 contains a logic flaw in CheckHostTrustController.getAuthority() that allows an attacker to bypass the security fix for CVE-2026-32303. The method hardcodes the URI scheme based on port number, causing HTTPS URLs with port 80 to produce the same authority string as HTTP URLs, which defeats both the consistency check and the HTTP block validation. An attacker with write access to a cloud-synced vault.cryptomator file can craft a Hub configuration where apiBaseUrl and authEndpoint use HTTPS with port 80 to pass auto-trust validation, while tokenEndpoint uses plaintext HTTP. The vault is auto-trusted without user prompt, and a network-positioned attacker can intercept the OAuth token exchange to access the Cryptomator Hub API as the victim. This issue has been fixed in version 1.19.2.

The record
Technical detail
CVSS v3.1
4.8 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:N/A:N
CVSS v4.0
Not supplied
EPSS
0.00140 · 3.1th percentile
Weaknesses
CWE-305 · Authentication Bypass by Primary Weakness; CWE-319 · Cleartext Transmission of Sensitive Information
Published
2026-04-16T21:12Z
EPSS history
Timeline
  • 16 APR 21:12Z
    Cryptomator Hub OAuth token exchange HTTP downgrade via getAuthority() scheme confusion (CVE-2026-32303 bypass)
    cvelistv5