CVE-2021-21265 - CVE House
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Status published Medium CVE-2021-21265

October CMS vulnerable to Potential Host Header Poisoning on misconfigured servers

Vulnerability Description

October is a free, open-source, self-hosted CMS platform based on the Laravel PHP Framework. In October before version 1.1.2, when running on poorly configured servers (i.e. the server routes any request, regardless of the HOST header to an October CMS instance) the potential exists for Host Header Poisoning attacks to succeed. This has been addressed in version 1.1.2 by adding a feature to allow a set of trusted hosts to be specified in the application. As a workaround one may set the configuration setting cms.linkPolicy to force.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

october
Vulnerable Versions:
< 1.1.2

Timeline

Official Publish: March 10th, 2021
Last Modified: May 29th, 2025
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N

Weaknesses (CWE)

CWE-644

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.