Sense of Security - Security Advisory - SOS-13-003 Release Date. 10-Sep-2013 Last Update. - Vendor Notification Date. 27-Sep-2012 Product. Juniper Junos J-Web Platform. Junos Affected versions. All builds prior to 2013-02-28 are affected Severity Rating. Medium Impact. Privilege escalation Attack Vector. From remote with read-only authentication Solution Status. Vendor patch (not verified by SOS) Disable J-Web or limit access CVE reference. CVE - not yet assigned Details. The J-Web is a GUI based network management application used on Junos devices. The web application is vulnerable to a remote code execution vulnerability which permits privilege escalation. The file/jsdm/ajax /port.php allows execution of arbitrary user supplied PHP code via the rs POST parameter. Code executes with UID=0 (root) privileges, however you are confined to a chroot. Privilege escalation can be achieved by waiting for an administrator to log in and reading the contents of /tmp to hijack their session. Proof of Concept. Code execution: Execute a command inside the Chroot: POST /jsdm/ajax/port.php rs=exec&rsargs=echo “hello” Privilege escalation: Read /tmp and hijack a session POST /jsdm/ajax/port.php rs=file_get_contents&rsargs=/tmp Solution. All Junos OS software releases built on or after 2013-02-28 have fixed this specific issue. This fix has not been validated by SOS. As a workaround disable J-Web, or limit access to only trusted hosts. This issue is being tracked as PR 826518 and is visible on the Juniper Customer Support website. Discovered by. Sense of Security Labs. About us. Sense of Security is a leading provider of information security and risk management solutions. Our team has expert skills in assessment and assurance, strategy and architecture, and deployment through to ongoing management. We are Australia's premier application penetration testing firm and trusted IT security advisor to many of the country's largest organisations.