SRC-2018-0006 : Synology Photo Station SYNOPHOTO_Flickr_MultiUpload Race Condition File Write Remote Code Execution Vulnerability

CVE ID:

N/A

CVSS Score:

6.5, (AV:N/AC:L/Au:N/C:P/I:P/A:P)

Affected Vendors:

Synology

Affected Products:

Disk Station Manager (DSN)

Vulnerability Details:

This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Synology Photo Station. Although authentication is required to exploit this vulnerability, the existing authentication mechanism can be bypassed.

The specific flaw exists within the SYNOPHOTO_Flickr_MultiUpload function. When parsing the prog_id parameter, the application does not properly validate a user-supplied string before using it to execute a call to file_put_contents. An attacker can leverage this vulnerability to execute code under the context of the PhotoStation user.

Vendor Response:

Synology has issued an update to correct these vulnerabilities. More details can be found at:
https://www.synology.com/en-global/support/security/Synology_SA_18_02

Disclosure Timeline:

• 2017-12-19 – Verified and sent to Delta Industrial Automation
• 2018-01-14 – Coordinated public release of advisory

Proof of Concept:

/pocs/src-2018-{0005,0006}.py.txt

Credit:

This vulnerability was discovered by Steven Seeley (mr_me) of Offensive Security