The vulnerability stems from the SVG exporter inserting a user-controlled fill‑color value into a shell command that is executed via child_process.exec. If an attacker can add shell metacharacters to this field, the exported ppmcolormask command will run arbitrary shell commands with the privileges of the exporter service. The result is uncontrolled code execution, which can lead to full system compromise for the service owner.

Penpot versions before 2.18.0 are impacted. Users of the open‑source design platform who have the ability to edit a file or access a publicly shared link that points to a malicious file are at risk.

The CVSS score of 9.9 indicates critical severity. EPSS data is not available and the vulnerability is not listed in CISA KEV catalog, but the absence of exploit data does not reduce the risk. The likely attack vector is that an authenticated user who can edit a file or any user who can trigger an export via a shared link can supply malicious content. Once the export is performed, the attacker’s shell commands execute with the service’s privileges. The lack of mitigations in older versions means exploitation is straightforward when the conditions are met.