CVE-2026-54243 is a medium-severity (CVSS 6.1) CWE-1236 vulnerability in statamic/cms. A fix is available for statamic/cms — see the affected versions and patch details below.
Statamic: CSV formula injection in form submission exports
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-54243.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2026-54243 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 395,249 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
statamic/cms🐘statamic/cmsReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
Impact
Form submission values were not neutralized for spreadsheet formula characters when exported to CSV. A submission containing a value beginning with a formula trigger character (e.g. = , + , - , @ ) could be interpreted as a live formula when a Control Panel user opens the export in a spreadsheet application. Form submissions can come from unauthenticated front-end visitors, so the malicious value can be supplied by an anonymous user and is later triggered by an editor opening the export.
Exploitation affects the spreadsheet application used to open the export, not the Statamic application or server; the data at risk is the form submission data the exporting user is already authorized to view.
Patches
This has been fixed in 5.73.24 and 6.20.1.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | statamic/cms | ≥ 6.0.0&&< 6.20.1 | 6.20.1composer require statamic/cms:^6.20.1 |
| 🐘Packagist | statamic/cms | all versions | 5.73.24composer require statamic/cms:^5.73.24 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for statamic/cms, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update statamic/cms to 6.20.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-54243 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Frequently Asked Questions
Is CVE-2026-54243 in your dependencies?
Find it across Packagist, including transitive dependencies.