CVE-2016-7521 in ImageMagick
Summary
by MITRE
Heap-based buffer overflow in coders/psd.c in ImageMagick allows remote attackers to cause a denial of service (out-of-bounds read) via a crafted PSD file.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 07/04/2024
The vulnerability identified as CVE-2016-7521 represents a critical heap-based buffer overflow flaw within ImageMagick's PSD file handling component. This issue resides in the coders/psd.c file where the software fails to properly validate input data when processing Photoshop Document format files. The flaw manifests as an out-of-bounds read condition that can be triggered by maliciously crafted PSD files, potentially leading to system instability and denial of service conditions. The vulnerability demonstrates a classic memory safety issue where insufficient bounds checking allows arbitrary data access beyond allocated memory boundaries.
This buffer overflow vulnerability operates at the core of ImageMagick's image processing pipeline, specifically targeting the PSD file format parser. When the software encounters a malformed PSD file, it attempts to read data from memory locations that have not been properly validated or allocated, resulting in an out-of-bounds memory access pattern. The heap-based nature of this vulnerability indicates that the memory corruption occurs within dynamically allocated memory segments, making the exploitation more complex but potentially more impactful than stack-based buffer overflows. The flaw essentially allows an attacker to manipulate memory access patterns and potentially execute arbitrary code or cause system crashes through carefully constructed input files.
The operational impact of CVE-2016-7521 extends beyond simple denial of service scenarios, as it represents a significant security risk for systems that process untrusted image files. Web applications, content management systems, and file processing services that utilize ImageMagick for image handling become vulnerable to remote exploitation. The vulnerability can be leveraged by attackers to cause system crashes, application instability, or potentially achieve privilege escalation depending on the execution environment. Systems running ImageMagick in server environments where users can upload files pose the highest risk, as attackers can craft malicious PSD files to compromise system availability and potentially execute malicious code within the application context.
Mitigation strategies for this vulnerability should focus on immediate patching of ImageMagick installations to the latest versions that contain the necessary memory validation fixes. Organizations should implement strict file validation procedures and consider implementing sandboxing mechanisms when processing untrusted image files. Network-level controls such as content filtering and file type restrictions can provide additional layers of protection. The vulnerability aligns with CWE-121, heap-based buffer overflow, and demonstrates characteristics consistent with attack patterns documented in the MITRE ATT&CK framework under the T1203 technique for legitimate program execution. Regular security assessments and vulnerability scanning should be implemented to identify systems running vulnerable versions of ImageMagick and ensure proper remediation. The remediation process should include comprehensive testing to verify that patched systems handle malformed PSD files without crashing or exhibiting memory corruption behaviors.