CVE-2026-42267
Kimai: Formula Injection via tag names in XLSX export
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.
INFO
Published Date :
May 8, 2026, 4:16 a.m.
Last Modified :
May 8, 2026, 4:16 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update Kimai to version 2.54.0 or later.
- Avoid opening XLSX files from untrusted sources.
- Review user permissions for tag creation.
- Sanitize tag names for formula characters.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-42267.
| URL | Resource |
|---|---|
| https://github.com/kimai/kimai/releases/tag/2.54.0 | |
| https://github.com/kimai/kimai/security/advisories/GHSA-3xc2-h5r3-wv3r |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-42267 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-42267
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-42267 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-42267 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by [email protected]
May. 08, 2026
Action Type Old Value New Value Added 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. Added CVSS V4.0 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 Added CWE CWE-1236 Added Reference https://github.com/kimai/kimai/releases/tag/2.54.0 Added Reference https://github.com/kimai/kimai/security/advisories/GHSA-3xc2-h5r3-wv3r