CVE-2021-21264: Bypass of fix for CVE-2020-26231, Twig sandbox escape

medium Affects october/cms. Feed 2026.10.29.4, updated 2026-10-29; published 2021-05-04; advisory modified 2026-07-08.

Bypass of fix for CVE-2020-26231, Twig sandbox escape

Package: october/cms Composer
Affected versions: >=1.0.471 and <1.0.472 or >=1.1.1 and <1.1.2
Fixed in: 1.0.472, 1.1.2
Severity: medium CVSS 5.2
Exploitation: not on CISA KEV · EPSS 0% (18.1th percentile)
Published: 2021-05-04
Source: osv.dev

References

CWE-862

NVD record october/cms 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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CVE-2020-15246 high Local File Inclusion by unauthenticated users same package: october/cms
CVE-2020-5296 medium Arbitrary File Deletion vulnerability in OctoberCMS same package: october/cms
CVE-2020-5297 low Upload whitelisted files to any directory in OctoberCMS same package: october/cms
CVE-2020-15247 medium Twig Sandbox Escape by authenticated users with access to editing CMS templates when safem same package: october/cms