CVE-2026-33046 in Indico
Summary
by MITRE • 03/24/2026
Indico is an event management system that uses Flask-Multipass, a multi-backend authentication system for Flask. In versions prior to 3.3.12, due to vulnerabilities in TeXLive and obscure LaTeX syntax that allowed circumventing Indico's LaTeX sanitizer, it is possible to use specially-crafted LaTeX snippets which can read local files or execute code with the privileges of the user running Indico on the server. Note that if server-side LaTeX rendering is not in use (ie `XELATEX_PATH` was not set in `indico.conf`), this vulnerability does not apply. It is recommended to update to Indico 3.3.12 as soon as possible. It is also strongly recommended to enable the containerized LaTeX renderer (using `podman`), which isolates it from the rest of the system. As a workaround, remove the `XELATEX_PATH` setting from `indico.conf` (or comment it out or set it to `None`) and restart the `indico-uwsgi` and `indico-celery` services to disable LaTeX functionality.
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Analysis
by VulDB Data Team • 03/28/2026
CVE-2026-33046 represents a critical server-side request forgery vulnerability within the Indico event management system that leverages flaws in LaTeX processing capabilities. This vulnerability specifically affects versions prior to 3.3.12 and stems from inadequate sanitization of LaTeX input within the Flask-Multipass authentication framework. The flaw exploits weaknesses in TeXLive's LaTeX implementation combined with obscure LaTeX syntax patterns that bypass the system's built-in sanitization mechanisms. Attackers can craft malicious LaTeX snippets that, when processed by the server, gain the ability to read local files or execute arbitrary code with the privileges of the Indico service account running on the server. The vulnerability's exploitation requires that server-side LaTeX rendering be enabled through the XELATEX_PATH configuration parameter, making it conditional rather than universal across all deployments. This aligns with CWE-77 and CWE-94 categories, representing code injection and improper input validation vulnerabilities respectively. The attack vector demonstrates characteristics consistent with ATT&CK technique T1059.007 for command and scripting interpreter usage, as the malicious LaTeX content can be used to execute system commands through the LaTeX rendering pipeline.
The operational impact of this vulnerability extends beyond simple privilege escalation to potentially compromise entire server infrastructures when Indico is deployed in production environments. The ability to read local files means attackers can access sensitive configuration files, database credentials, and other system resources that may contain authentication tokens, private keys, or other confidential information. Code execution capabilities with the service account privileges create a pathway for persistent access, lateral movement, and potential data exfiltration. Organizations using Indico with LaTeX rendering enabled face significant risk, particularly in environments where the service account has elevated permissions or where Indico shares infrastructure with other critical systems. The vulnerability's remediation path requires immediate version updates to 3.3.12 or later, which includes patches for the LaTeX sanitization issues. However, the recommended approach goes beyond simple patching to include architectural isolation through containerized LaTeX rendering using podman, which addresses the root cause by creating network and file system isolation between the LaTeX processing environment and the main Indico application. This approach aligns with security best practices for sandboxing and principle of least privilege enforcement.
The vulnerability's detection and mitigation strategy requires comprehensive system assessment to identify affected deployments and configuration states. Organizations must verify that XELATEX_PATH is properly configured in their indico.conf files and ensure that the containerized rendering approach is implemented as a security control. The recommended workaround of commenting out XELATEX_PATH provides immediate protection but removes legitimate LaTeX functionality, which may impact user experience. System administrators should implement monitoring for unusual file access patterns or command execution attempts that might indicate exploitation attempts. The security implications extend to compliance requirements where unauthorized file access or code execution could constitute violations of data protection regulations and security standards. Implementation of the containerized LaTeX renderer not only addresses this specific vulnerability but also provides defense-in-depth against similar future vulnerabilities by isolating the rendering process. Regular security assessments and vulnerability scanning should include checks for proper configuration of LaTeX rendering components, ensuring that any future patches or updates are properly applied and that isolation mechanisms remain effective. The vulnerability serves as a reminder of the importance of validating input processing in web applications and the need for robust sanitization of user-provided content, particularly when dealing with complex markup languages that can be exploited for code execution.