CVE-2026-49449 (GCVE-0-2026-49449)

Vulnerability from cvelistv5 – Published: 2026-09-21 20:52 – Updated: 2026-09-28 20:15
VLAI
Title
Joplin: KaTeX `trust:true` enables URL-allowlist bypass leading to NTLMv2 credential theft via UNC path on Windows
Summary
Joplin is an open source note-taking and to-do application that organises notes and lists into notebooks. From 1.4.0 until 3.7.2, packages/renderer/MdToHtml/rules/katex.ts enables KaTeX's trust option for note content, allowing a note author to place a \href URL into rendered output without passing Joplin's normal URL allowlist. On Windows, clicking a link whose target is an attacker-controlled UNC path causes pathExists() to initiate SMB authentication and disclose the current user's NTLMv2 challenge-response without a warning. The unfiltered URL can also invoke other registered URL handlers, but the credential disclosure through KaTeX \href is the distinguishing demonstrated impact. This issue is fixed in version 3.7.2.
Severity
2.5 (Low)
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-28 20:15 UTC
CWE
  • CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
  • CWE-522 - Insufficiently Protected Credentials
  • CWE-829 - Inclusion of Functionality from Untrusted Control Sphere
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7994 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
laurent22 joplin Affected: >= 1.4.0, < 3.7.2
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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