CVE-2026-42267

Kimai is an open-source time tracking application. From version 2.27.0 to before version 2.54.0, any ROLE_USER can create a tag with a formula string as its name (e.g. =SUM(54+51)) via POST /api/tags and assign it to a timesheet. When an admin exports timesheets to XLSX, ArrayFormatter.formatValue() joins tag names with implode() and returns the result unchanged. OpenSpout promotes any =-prefixed string to a FormulaCell, writing <f>SUM(54+51)</f> into the XLSX archive. Excel evaluates the formula when the file is opened. This issue has been patched in version 2.54.0.

Affected products

Kimai, Openspout

Kimai

< 2.54.0

Fix

Available

CVSS 4.0

6.8 MEDIUM

CVSS 3.1

5.7 MEDIUM

EPSS

0.2% (12th percentile)

Weakness

CWE-1236

NVD status

Analyzed

Published

2026-05-08

No exploit for CVE-2026-42267 has been indexed yet. Our index is built from live traffic and upstream syncs, so this page can only say what it knows — not that no exploit exists.