CVE-2023-39007: /ui/cron/item/open in the Cron component of OPNsense Community Edition before 23.7 and Business Edition before 23.4.2 allows XSS via openAction in…

PriorityP352critical9.6CVSS 3.1

AVNACLPRNUIRSCCHIHAH

EXPLOIT

EPSS

2.31%

81.3th percentile

/ui/cron/item/open in the Cron component of OPNsense Community Edition before 23.7 and Business Edition before 23.4.2 allows XSS via openAction in app/controllers/OPNsense/Cron/ItemController.php.

Affected

1 ranges

Vendor	Product	Version range	Fixed in
opnsense	opnsense	< 23.7	23.7

Detection & IOCsextracted from sources · hover to see the quote

url/ui/cron/item/open/0'+alert(document.domain)+'↗

path/ui/cron/item/open↗

pathapp/controllers/OPNsense/Cron/ItemController.php↗

→Detect exploitation attempts by matching the XSS payload pattern in HTTP requests to /ui/cron/item/open — look for single-quote injection with alert() in the path parameter.
→Confirm successful XSS reflection by checking the response body for the unescaped payload string echoed back inside an openDialog() call.
→Use Shodan/FOFA queries to identify exposed OPNsense instances as potential targets: search for title 'OPNsense' or 'opnsense'.
→The vulnerability requires authentication; monitor for POST login requests immediately followed by GET requests to /ui/cron/item/open with non-numeric or quote-containing path segments.

·The vulnerability affects OPNsense Community Edition before 23.7 and Business Edition before 23.4.2 only; patched versions are not vulnerable.
·Exploitation requires an authenticated session; unauthenticated scanning will not trigger the vulnerable code path.

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