CVE-2021-21265

October CMS vulnerable to Potential Host Header Poisoning on misconfigured servers

HIGH
7.5
CVSS Score
Published: March 10, 2021 at 09:15 PM UTC
Updated: June 17, 2026 at 03:35 AM UTC
1 product affected across 1 vendorOctober

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Severity
HIGH7.5
Exploit prediction
EPSS 2%

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 1.1.2
Affected range stops below 1.1.2, so it looks safe — our inference, not a vendor statement

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-644

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