CVE-2026-116158 in ImageMagick
Summary
by MITRE • 10/25/2026
ImageMagick before 7.1.2-33 contains a memory leak vulnerability in the magick compare command caused by missing cleanup when an operation fails. Attackers can supply inputs that trigger repeated failed compare operations to exhaust memory and cause denial of service.
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Analysis
by VulDB Data Team • 10/25/2026
The identified vulnerability resides within ImageMagick, specifically affecting versions prior to 7.1.2-33, targeting the magick compare command utility. This component is responsible for comparing two images to determine their differences or similarities, a function widely utilized in automated image processing pipelines and content management systems. The core technical flaw stems from improper resource management during error handling sequences within this specific module. When an operation fails due to malformed input or internal logic errors, the software neglects to release allocated memory buffers that were prepared for the comparison task. This oversight results in a classic memory leak scenario where heap allocations accumulate over time without being freed back to the operating system.
From a technical perspective, this flaw represents a failure in cleanup routines following exceptional conditions. In robust software design, any branch of execution that allocates dynamic memory must ensure corresponding deallocation occurs upon both success and failure paths. The absence of these cleanup operations means that each failed invocation of the compare command leaves behind orphaned memory blocks. While a single instance may have negligible impact on system stability, an attacker can exploit this behavior by crafting specific inputs designed to consistently trigger comparison failures. By repeatedly submitting such malicious payloads, the attacker forces the application to continuously allocate new memory while failing to reclaim it, leading to progressive resource exhaustion.
The operational impact of this vulnerability is primarily a denial of service condition affecting both local and potentially remote services depending on how ImageMagick is integrated into an environment. As memory consumption grows unchecked, system performance degrades significantly due to increased swapping or pressure on available RAM. Eventually, the process may be terminated by the operating system's out-of-memory killer, causing service interruption for legitimate users. In cloud-native environments where containers are restarted upon failure, this can lead to rapid resource churn and potential billing spikes if not monitored. The vulnerability does not currently indicate a path for arbitrary code execution or privilege escalation but remains critical due to its ease of exploitation and direct impact on availability.
This issue aligns with Common Weakness Enumeration standard CWE-401, which describes missing release of memory after effective usage. It also relates to CWE-772, the lack of releasing resources before exiting a function. In terms of adversarial tactics, this vulnerability supports techniques associated with resource exhaustion attacks under the MITRE ATT&CK framework, specifically those aimed at disrupting service availability rather than compromising confidentiality or integrity. Attackers can leverage automated scripts to flood the target with malformed image data, exploiting the predictable nature of the memory leak to achieve sustained disruption.
Mitigation strategies should prioritize immediate patching to version 7.1.2-33 or later where these cleanup routines have been corrected by the developers. For environments unable to update immediately, implementing resource limits such as ulimits on Linux systems can restrict the maximum virtual memory size an ImageMagick process may consume, thereby containing the impact of the leak. Additionally, deploying a reverse proxy with rate limiting capabilities in front of services that utilize ImageMagick for image processing can help mitigate volumetric attacks by throttling incoming requests from suspicious sources. Regular monitoring of system resource usage and setting up alerts for abnormal memory growth patterns associated with image processing tasks will also aid in early detection and response to potential exploitation attempts.