In dotCMS, versions mentioned, a flaw in the NormalizationFilter does not strip double slashes (//) from URLs, potentially enabling bypasses for XSS and access controls. An example affected URL is https://demo.dotcms.com//html/portlet/ext/files/edit_text_inc.jsp , which should return a 404 response but didn't.
The oversight in the default invalid URL character list can be viewed at the provided GitHub link https://github.com/dotCMS/core/blob/master/dotCMS/src/main/java/com/dotcms/filters/NormalizationFilter.java#L37 .
To mitigate, users can block URLs with double slashes at firewalls or utilize dotCMS config variables.
Specifically, they can use the DOT_URI_NORMALIZATION_FORBIDDEN_STRINGS environmental variable to add // to the list of invalid strings.
Additionally, the DOT_URI_NORMALIZATION_FORBIDDEN_REGEX variable offers more detailed control, for instance, to block //html.* URLs.
Fix Version:23.06+, LTS 22.03.7+, LTS 23.01.4+
Conclusion & alert: CVE-2023-3042 is rated Low Risk (31/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.36%).Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
Exploit prediction scoring system (EPSS) score for CVE-2023-3042
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).