Projen up to 0.102.x Task Synthesis .projen/tasks.json os command injection

Summaryinfo

A vulnerability labeled as critical has been found in Projen up to 0.102.x. Affected by this vulnerability is an unknown functionality of the file .projen/tasks.json of the component Task Synthesis. The manipulation results in os command injection. This vulnerability was named CVE-2026-89066. The attack may be performed from remote. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Projen up to 0.102.x. It has been classified as critical. Affected is an unknown part of the file .projen/tasks.json of the component Task Synthesis. The manipulation with an unknown input leads to a os command injection vulnerability. CWE is classifying the issue as CWE-78. The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

Improper neutralization of special elements used in an OS command in the task synthesis component in projen before 0.103.0 might allow context-dependent attackers to execute arbitrary commands on a developer workstation or continuous integration runner via shell metacharacters in project configuration values and repository file names that are interpolated into generated task definitions. To remediate this issue, users should upgrade to version 0.103.0 and then re-synthesize the project so that .projen/tasks.json is regenerated with the corrected task definitions. Upgrading alone is not sufficient because the generated task definition file is committed to the repository.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-89066 since 09/10/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1202.

By approaching the search of inurl:.projen/tasks.json it is possible to find vulnerable targets with Google Hacking.

Upgrading to version 0.103.0 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

• Projen

Version

• 0.102

Website

• Product: https://github.com/projen/projen/

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Once again VulDB remains the best source for vulnerability data.

Discussion