CVE-2022-23491: Certifi Information Disclosure Flaw

CVE-2022-23491 Overview

CVE-2022-23491 is a Certificate Validation Bypass vulnerability affecting the Certifi Python package, a curated collection of Root Certificates used for validating the trustworthiness of SSL certificates while verifying the identity of TLS hosts. The vulnerability stems from the inclusion of TrustCor root certificates in the trust store, which were subsequently found to be associated with an organization that operated a business producing spyware.

Certifi version 2022.12.07 addresses this issue by removing TrustCor root certificates from the root store. This removal aligns with Mozilla's decision to remove these certificates from their trust store following an investigation prompted by media reporting about TrustCor's ownership and their connection to spyware operations.

Critical Impact

Applications using affected versions of Certifi may trust SSL/TLS certificates issued by TrustCor, potentially allowing malicious actors with TrustCor-issued certificates to perform man-in-the-middle attacks or impersonate trusted services.

Affected Products

• Certifi Python package (versions prior to 2022.12.07)
• NetApp E-Series Performance Analyzer
• NetApp Management Services for Element Software
• NetApp Management Services for NetApp HCI

Discovery Timeline

• 2022-12-07 - CVE-2022-23491 published to NVD
• 2025-02-12 - Last updated in NVD database

Technical Details for CVE-2022-23491

Vulnerability Analysis

This vulnerability is classified under CWE-345 (Insufficient Verification of Data Authenticity). The core issue lies in the trust chain mechanism of SSL/TLS certificate validation. When TrustCor root certificates were included in Certifi's trust store, any certificate signed by TrustCor Certificate Authorities would be automatically trusted by applications using the Certifi package.

The concern arose from investigations revealing that TrustCor's ownership was connected to operations that produced spyware. This raised serious questions about the integrity and trustworthiness of certificates issued under their authority. An attacker with access to TrustCor-issued certificates could potentially intercept encrypted communications or impersonate legitimate services to applications relying on Certifi for certificate validation.

Root Cause

The root cause of this vulnerability is the inclusion of root certificates from a Certificate Authority (TrustCor) whose trustworthiness came into question due to their ownership's involvement in spyware operations. Certificate Authorities are granted significant trust in the PKI ecosystem, and any compromise or questionable practices by a CA can have far-reaching security implications for all entities relying on certificates issued by that authority.

The Certifi project, which mirrors Mozilla's trust store for Python applications, needed to remove these certificates to maintain the integrity of the trust chain used by Python applications worldwide.

Attack Vector

The attack vector for this vulnerability is network-based and requires no user interaction. An attacker could exploit this vulnerability by:

1. Obtaining a valid certificate signed by TrustCor Certificate Authority
2. Using this certificate to impersonate a legitimate service
3. Intercepting communications from applications that trust TrustCor certificates through Certifi

Since Certifi is widely used in Python applications for SSL/TLS certificate validation, the potential attack surface includes any Python application that performs HTTPS requests or other TLS-protected communications using libraries like requests, urllib3, or similar packages that depend on Certifi.

The vulnerability allows for potential integrity compromise of encrypted communications, as applications would trust certificates that should no longer be considered trustworthy based on the CA's questionable business practices.

Detection Methods for CVE-2022-23491

Indicators of Compromise

• SSL/TLS connections validated using certificates issued by TrustCor Certificate Authority
• Applications establishing trusted connections with endpoints presenting TrustCor-signed certificates
• Unexpected certificate chains involving TrustCor root certificates in application logs

Detection Strategies

• Audit Python environments to identify Certifi package versions older than 2022.12.07
• Review dependency manifests (requirements.txt, Pipfile.lock, poetry.lock) for outdated Certifi versions
• Implement certificate transparency monitoring to detect TrustCor-issued certificates in your infrastructure
• Use software composition analysis (SCA) tools to identify vulnerable Certifi dependencies

Monitoring Recommendations

• Enable certificate chain logging in Python applications to capture CA information
• Monitor for network connections to endpoints presenting TrustCor-signed certificates
• Implement alerts for SSL/TLS connections involving certificates from deprecated Certificate Authorities

How to Mitigate CVE-2022-23491

Immediate Actions Required

• Upgrade Certifi to version 2022.12.07 or later using pip install --upgrade certifi
• Audit all Python applications and dependencies for outdated Certifi versions
• Review NetApp product deployments and apply vendor-recommended patches
• Verify certificate validation is functioning correctly after the upgrade

Patch Information

The fix is available in Certifi version 2022.12.07, which removes TrustCor root certificates from the trust store. For detailed information about the security advisory, refer to the GitHub Security Advisory. Mozilla's investigation findings are documented in the Mozilla Security Policy Discussion.

NetApp users should consult the NetApp Security Advisory for product-specific guidance on affected products including E-Series Performance Analyzer and Management Services.

Workarounds

• Manually remove TrustCor certificates from your certificate trust store if immediate upgrade is not possible
• Implement certificate pinning for critical connections to specific trusted endpoints
• Configure application-level certificate validation to explicitly reject TrustCor-issued certificates

# Upgrade Certifi to the patched version
pip install --upgrade certifi>=2022.12.07

# Verify the installed version
python -c "import certifi; print(certifi.__version__)"

# For virtual environments, update requirements
pip freeze | grep certifi