Kimai up to 2.53.x /api/tags ArrayFormatter.formatValue csv injection

Summaryinfo

A vulnerability marked as critical has been reported in Kimai up to 2.53.x. The impacted element is the function ArrayFormatter.formatValue of the file /api/tags. Performing a manipulation results in csv injection. This vulnerability is known as CVE-2026-42267. Remote exploitation of the attack is possible. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Kimai up to 2.53.x. It has been classified as critical. This affects the function ArrayFormatter.formatValue of the file /api/tags. The manipulation with an unknown input leads to a csv injection vulnerability. CWE is classifying the issue as CWE-1236. The product saves user-provided information into a Comma-Separated Value (CSV) file, but it does not neutralize or incorrectly neutralizes special elements that could be interpreted as a command when the file is opened by a spreadsheet product. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

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 SUM(54+51) into the XLSX archive. Excel evaluates the formula when the file is opened. This issue has been patched in version 2.54.0.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-42267 since 04/26/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. Technical details of the vulnerability are known, but there is no available exploit.

It is declared as proof-of-concept.

Upgrading to version 2.54.0 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Name

• Kimai

Version

• 2.0
• 2.1
• 2.2
• 2.3
• 2.4
• 2.5
• 2.6
• 2.7
• 2.8
• 2.9
• 2.10
• 2.11
• 2.12
• 2.13
• 2.14
• 2.15
• 2.16
• 2.17
• 2.18
• 2.19
• 2.20
• 2.21
• 2.22
• 2.23
• 2.24
• 2.25
• 2.26
• 2.27
• 2.28
• 2.29
• 2.30
• 2.31
• 2.32
• 2.33
• 2.34
• 2.35
• 2.36
• 2.37
• 2.38
• 2.39
• 2.40
• 2.41
• 2.42
• 2.43
• 2.44
• 2.45
• 2.46
• 2.47
• 2.48
• 2.49
• 2.50
• 2.51
• 2.52
• 2.53

Website

• Product: https://github.com/kimai/kimai/

CPE 2.3info

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