CVE-2026-105403 in ImageMagick
Summary
by MITRE • 10/08/2026
ImageMagick before 6.9.13-56 and 7.x before 7.1.2-31 allows a security policy bypass when a policy uses coder, rather than module, as its domain. An attacker can supply a crafted image to evade coder-based policy restrictions, causing ImageMagick to process formats the administrator intended to block.
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Analysis
by VulDB Data Team • 10/08/2026
The vulnerability identified in versions of ImageMagick prior to 6.9.13-56 and 7.x before 7.1.2-31 represents a critical security policy bypass mechanism rooted in the application's configuration parsing logic. ImageMagick utilizes a robust policy system designed to restrict access to specific image formats, file types, or operations based on administrator-defined rules. These policies are typically defined using domains such as coder, module, path, or pattern to control which resources can be accessed during processing tasks. The core technical flaw lies in the inconsistency between how these restrictions are declared and how they are enforced within the codebase. Specifically, when an administrator configures a policy rule targeting a specific image format by specifying it under the coder domain rather than the module domain, the enforcement mechanism fails to apply the restriction correctly during certain processing operations. This discrepancy allows crafted inputs to slip through the intended security controls, effectively neutralizing the protective measures put in place by system administrators.
From an operational perspective, this vulnerability enables attackers to bypass access control restrictions that are meant to prevent the processing of dangerous or unsupported file formats. By supplying a specially constructed image file, an attacker can exploit this logic error to force ImageMagick to process data types that were explicitly blocked by policy. This capability is particularly dangerous in environments where ImageMagick is used as part of web applications for handling user-uploaded images, such as profile picture uploads or document conversion services. If the application relies on these policies to mitigate risks associated with formats like SVG, EPS, or PDF which may contain executable code or trigger other vulnerabilities, a successful bypass could lead to remote code execution, denial of service, or information disclosure. The attacker does not need elevated privileges; they only require the ability to submit input data that triggers this parsing inconsistency, making it a viable attack vector for unauthenticated adversaries in many deployment scenarios.
This flaw aligns with CWE-284 Improper Access Control and CWE-755: Improper Handling of Exceptional Conditions, as the software fails to correctly enforce security restrictions due to flawed logic handling different policy domains. In terms of offensive tactics, this behavior is consistent with ATT&CK technique T1068 Exploitation for Privilege Escalation or more broadly T1190 Exploit Public-Facing Application if leveraged in a web context to gain initial access. The root cause stems from the internal mapping between coder names and module implementations not being strictly validated against policy rules defined under the coder domain, leading to an authorization bypass where the system assumes compliance with policies that were technically misconfigured or ambiguously interpreted by the parser.
To mitigate this vulnerability, organizations must upgrade ImageMagick to version 6.9.13-56 or later for the legacy branch and version 7.1.2-31 or later for the v7 branch immediately upon availability from official repositories. In addition to upgrading, administrators should review their policy.xml configuration files to ensure that restrictions are consistently applied across both coder and module domains where applicable. It is recommended to adopt a defense-in-depth strategy by validating file types not only through ImageMagick policies but also via MIME type checks at the application layer before passing data to image processing libraries. Regular auditing of security configurations against current best practices and staying informed about vendor advisories are essential steps to maintain robust protection against such configuration-based bypasses in critical infrastructure components handling untrusted media inputs.