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TI-2026-36604 Aliases CVE-2026-49449

Joplin: KaTeX `trust:true` enables URL-allowlist bypass leading to NTLMv2 credential theft via UNC path on Windows

Priority MEDIUM 46CWE-200Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
Required
Attack complexity
High
Impact type
Information disclosure, Code execution
Confidentiality · integrity · availability
Low · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-200 and CWE-829.

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00196 9th percentileScored 2026-11-07
Fix Fixed joplin (laurent22): 3.7.2

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

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

Affected products

VendorProductAffected versionsFixed inStatusSource
laurent22joplin1.4.0 to before 3.7.23.7.2Patch availableCNA
  • joplin Vendorlaurent22 Affected 1.4.0 to before 3.7.2 Fixed in 3.7.2 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:joplin_project:joplin:*:*:*:*:*:*:*:*——laurent22
  • cpe:2.3:a:joplin_project:joplin:*:*:*:*:*:*:*:* Versions — — ·laurent22

Remediation

  • Fix · CNA joplin (laurent22) Fixed in 3.7.2

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-49449

References

Other 3

  • TI-2023-24472 Arbitrary code execution on click of PDF links in Joplin CVSS 3.1CRITICAL 9.0
  • TI-2024-32950 Remote Code Execution on click of <a> Link in markdown preview CVSS 3.1CRITICAL 9.6
  • TI-2024-27054 Joplin has a parsing error leading to Cross-site Scripting (XSS) CVSS 3.1CRITICAL 9.7
  • TI-2026-34297 Joplin: SSO Auth Code Login Missing Rate Limiting — 9-Digit Numeric Code Brute-Forceable via Unprotected Endpoint CVSS 4.0CRITICAL 9.1
  • TI-2025-17795 Cross-site Scripting (XSS) in Rich Text Editor allows arbitrary code execution in Joplin CVSS 3.1CRITICAL 9.6
  • TI-2025-19991 Privilege escalation in Joplin server via user patch endpoint CVSS 3.1HIGH 8.8
See all 39 →

Sources

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