CVE-2026-26067: October CMS has Safe Mode Bypass via CSS Preprocessor Compilers

medium Affects october/system. Feed 2026.10.29.3, updated 2026-10-29; published 2026-04-21; advisory modified 2026-05-05.

October CMS has Safe Mode Bypass via CSS Preprocessor Compilers

Package: october/system Composer
Affected versions: <3.7.14 or >=4.0.0 and <4.1.10
Fixed in: 3.7.14, 4.1.10
Severity: medium CVSS 4.9
Exploitation: not on CISA KEV · EPSS 0% (15.8th percentile)
Published: 2026-04-21
Source: osv.dev

References

CWE-184 CWE-200 CWE-22

NVD record october/system advisories

Am I affected?

Find out in one command. phpwarden checks your composer.lock against this advisory and 20,000+ others, ranked by real-world exploitation (CISA KEV + EPSS). Free, offline, open data.

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Install docs How findings are ranked

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CVE-2021-32649 high October/System authenticated file write leads to remote code execution same package: october/system
CVE-2021-41126 high Deleted Admin Can Sign In to Admin Interface same package: october/system