TI-2026-30580 Aliases CVE-2026-42267 GHSA-3xc2-h5r3-wv3r

Kimai: Formula Injection via tag names in XLSX export

MEDIUM 58CWE-1236Published 2026-05-08 · Updated 2026-05-08

Key facts

Attack vector: Network
Privileges required: Low
User interaction: Active
Attack complexity: Low
Attack requirements: None
Impact type: —
Confidentiality · integrity · availability: None · High · None
Fix status: Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.0022 12th percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by NVD

Fix Fixed kimai (kimai): 2.54.0kimai/kimai (Packagist): 2.54.0

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

Vendor	Product	Affected versions	Fixed in	Status	Source
kimai	kimai	2.27.0 to before 2.54.0	2.54.0	Patch available	CNA
—	kimai/kimai (Packagist)	2.27.0 to before 2.54.0	2.54.0	Patch available	GHSA-3xc2-h5r3-wv3r

kimai Vendorkimai Affected 2.27.0 to before 2.54.0 Fixed in 2.54.0 Patch available CNA
kimai/kimai (Packagist) Vendor— Affected 2.27.0 to before 2.54.0 Fixed in 2.54.0 Patch available GHSA-3xc2-h5r3-wv3r

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:kimai:kimai::::::::	2.27.0 to before 2.54.0	Vulnerable	kimai

cpe:2.3:a:kimai:kimai:*:*:*:*:*:*:*:* Versions 2.27.0 to before 2.54.0 Vulnerable ·kimai

Remediation

Fix · CNA kimai (kimai) Fixed in 2.54.0
Fix · GHSA-3xc2-h5r3-wv3r kimai/kimai (Packagist) Fixed in 2.54.0 Advisory →

Timeline

2026-10-02 Threatist record created from CVE-2026-42267
2026-10-03 Alias added: GHSA-3xc2-h5r3-wv3r

References

Exploit 1

https://github.com/kimai/kimai/security/advisories/GHSA-3xc2-h5r3-wv3r

Advisory 1

https://nvd.nist.gov/vuln/detail/CVE-2026-42267

Other 2

TI-2023-30240 Kimai 1.30.10 SameSite Cookie Vulnerability Session Hijacking CVSS 4.0HIGH 8.5
TI-2026-22900 Kimai: API invoice endpoint missing customer-level access control (IDOR) CVSS 3.1MEDIUM 6.5
TI-2026-29230 Kimai: Stored XSS via Incomplete HTML Attribute Escaping in Team Member Widget CVSS 3.1MEDIUM 5.4
TI-2019-15371 Kimai 2- persistent cross-site scripting (XSS) CVSS 4.0MEDIUM 5.1
TI-2026-29237 Kimai's User Preferences API allows standard users to modify restricted attributes: hourly_rate, internal_rate CVSS 3.1MEDIUM 4.3
TI-2026-30084 Kimai: Team API Missing Object-Level Authorization CVSS 3.1LOW 3.3

See all 13 →

Sources

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