CVE-2021-45847 in libslic3r
Summary
by MITRE • 01/25/2022
Several missing input validations in the 3MF parser component of Slic3r libslic3r 1.3.0 can each allow an attacker to cause an application crash using a crafted 3MF input file.
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Analysis
by VulDB Data Team • 01/28/2022
The vulnerability identified as CVE-2021-45847 resides within the 3MF parser component of Slic3r libslic3r version 1.3.0, representing a critical security flaw that undermines the software's input validation mechanisms. This issue manifests through multiple missing validation checks that fail to properly sanitize or verify incoming 3MF files, creating exploitable entry points for malicious actors seeking to disrupt the application's normal operation. The 3MF format, which stands for 3D Manufacturing Format, serves as a standard for exchanging 3D printing data between different software platforms, making this vulnerability particularly concerning for 3D printing workflows and manufacturing environments.
The technical nature of this vulnerability stems from insufficient input validation routines within the parser's handling of 3MF files, which are commonly used in 3D printing applications to store model data, print settings, and other manufacturing parameters. When the parser encounters malformed or specially crafted 3MF input files, the absence of proper validation leads to unhandled exceptions or memory access violations that ultimately result in application crashes. This type of vulnerability falls under the CWE-20 category of "Improper Input Validation," specifically manifesting as a failure to validate data integrity before processing. The flaw demonstrates characteristics consistent with buffer overflows, null pointer dereferences, or other memory corruption issues that occur when software fails to properly handle unexpected input structures.
The operational impact of CVE-2021-45847 extends beyond simple application instability, potentially disrupting 3D printing workflows and manufacturing processes that rely on Slic3r for preparing print jobs. Attackers could exploit this vulnerability to perform denial-of-service attacks against 3D printing systems, causing production delays or complete system outages in industrial environments. In professional settings where 3D printing is integrated into automated manufacturing pipelines, such a vulnerability could lead to significant financial losses and operational disruptions. The vulnerability's exploitation requires only the delivery of a crafted 3MF file, making it particularly dangerous as it can be triggered through simple file sharing or automated download mechanisms, aligning with ATT&CK technique T1203 for "Exploitation for Client Execution" and potentially T1499 for "Endpoint Denial of Service" in enterprise security contexts.
Mitigation strategies for CVE-2021-45847 should prioritize immediate software updates to versions that address the missing input validation issues within the 3MF parser component. Organizations should implement strict file validation procedures before processing 3MF inputs, including signature verification and format compliance checks to prevent malformed files from reaching the vulnerable parser. Network-level controls such as file type restrictions and content filtering can provide additional defense-in-depth measures. Security teams should also consider implementing monitoring solutions that detect unusual application crash patterns or resource consumption spikes that might indicate exploitation attempts. The vulnerability's remediation aligns with industry best practices for secure coding standards, particularly those emphasizing the principle of least privilege and input sanitization, and should be integrated into comprehensive vulnerability management programs that follow frameworks such as NIST SP 800-34 or ISO 27001 security controls.