An issue was discovered in Deskpro before 2019.8.0. This product enables administrators to modify the helpdesk interface by editing /portal/api/style/edit-theme-set/template-sources theme templates, and uses TWIG as its template engine. While direct access to self and _self variables was not permitted, one could abuse the accessible variables in one's context to reach a native unserialize function via the code parameter. There, on could pass a crafted payload to trigger a set of POP gadgets in order to achieve remote code execution.

References

• https://nvd.nist.gov/vuln/detail/CVE-2020-11467
• https://blog.redforce.io/attacking-helpdesks-part-1-rce-chain-on-deskpro/
• https://support.deskpro.com/en/news/posts/deskpro-security-update-2019-09
• https://support.deskpro.com/en/news/posts/deskpro-v2019-8-0-released-security-update