Description
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: kimai
References3
- github.com/kimai/kimai/security/advisories/GHSA-3xc2-h5r3-wv3r ExploitMitigationVendor Advisory
- github.com/kimai/kimai/security/advisories/GHSA-3xc2-h5r3-wv3r ExploitMitigationVendor Advisory
- github.com/kimai/kimai/releases/tag/2.54.0 ProductRelease Notes
Metrics
- CVSS 3.1
-
5.7
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:H/A:N - CVSS 4.0
-
5.4
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 13 · as of 13 November 2026
- CWE
- CWE-1236
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