Cyber Resilience

CVE-2021-21265

Medium

Published: 10 March 2021

Published
10 March 2021
Modified
30 May 2025
KEV Added
Patch
CVSS Score v3.1 6.8 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N
EPSS Score 0.0051 66.8th percentile
Risk Priority 14 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-21265 is a medium-severity Improper Neutralization of HTTP Headers for Scripting Syntax (CWE-644) vulnerability in Octobercms October. Its CVSS base score is 6.8 (Medium).

Operationally, ranked in the top 33.2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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…

more

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.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

octobercms
october
≤ 1.1.2

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References