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TI-2026-48454 Aliases CVE-2026-68899

Wekan: File Upload MIME Type Validation Bypass — Stored XSS via Missing System Binary Fallback

Priority MEDIUM 40CWE-434Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-434.

Summary

Wekan is open source kanban built with Meteor. Prior to 9.90, isFileValid() in models/fileValidation.js used the Unix file command for content-based MIME detection, but detectMimeFromFile() silently returned undefined when that binary was unavailable and the validation fell back to the attacker-controlled fileObj.type supplied through server/routes/attachmentApi.js. On deployments with WITH_API=true and no file binary, an authenticated board member could label HTML containing JavaScript as image/png, bypass the dangerous MIME check, and store active content under the Wekan origin for execution when another user opened it. Version 9.90 adds looksLikeDangerousMarkup() to inspect file bytes and force dangerous-content scanning when MIME detection is unavailable. This issue is fixed in version 9.90.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00527 44th percentileScored 2026-11-07
Fix Fixed wekan (wekan): 9.90

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
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
wekanwekanbefore 9.909.90Patch availableCNA
  • wekan Vendorwekan Affected before 9.90 Fixed in 9.90 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:wekan_project:wekan:*:*:*:*:*:*:*:*——wekan
  • cpe:2.3:a:wekan_project:wekan:*:*:*:*:*:*:*:* Versions — — ·wekan

Remediation

  • Fix · CNA wekan (wekan) Fixed in 9.90

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-68899

References

  • TI-2026-40177 Improper authentication in wekan CVSS 3.1CRITICAL 9.8
  • TI-2026-37989 Wekan: OIDC Account Takeover via Unconditional Email-Based Account Merge in onCreateUser hook CVSS 4.0CRITICAL 9.2
  • TI-2026-48308 Improper privilege management in wekan CVSS 3.1HIGH 8.8
  • TI-2026-48305 Wekan: SSRF filter bypass via DNS-resolving hostname in outgoing webhooks (incomplete fix of CVE-2026-53446) CVSS 3.1HIGH 8.5
  • TI-2026-39911 Improper access control in wekan CVSS 3.1HIGH 8.5
  • TI-2026-01855 WeKan Activity Publication activities.js LinkedBoardActivitiesBleed information disclosure CVSS 4.0MEDIUM 6.9
See all 59 →

Sources

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