CVE-2018-4953 in Acrobat Reader
Summary
by MITRE
Adobe Acrobat and Reader versions 2018.011.20038 and earlier, 2017.011.30079 and earlier, and 2015.006.30417 and earlier have a Type Confusion vulnerability. Successful exploitation could lead to arbitrary code execution in the context of the current user.
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Analysis
by VulDB Data Team • 07/22/2024
Adobe Acrobat and Reader contain a type confusion vulnerability that affects multiple versions across different release cycles. This vulnerability stems from improper handling of object types during runtime execution, creating opportunities for attackers to manipulate memory operations. The flaw occurs when the application fails to properly validate type information during object manipulation, allowing malicious input to be interpreted as different data types than intended. Such type confusion vulnerabilities are particularly dangerous because they can lead to memory corruption that enables arbitrary code execution.
The technical implementation of this vulnerability involves the application's object model where different classes or data structures are not properly distinguished during runtime operations. When processing maliciously crafted PDF documents, the software incorrectly handles type information, potentially allowing an attacker to overwrite memory locations or execute unintended code sequences. This type confusion typically manifests when the application attempts to perform operations on objects that have been manipulated to appear as different types than their actual declaration. The vulnerability exists in the parsing and rendering components of the software, specifically in how it processes complex object hierarchies and manages memory allocation for various data types.
Successful exploitation of this vulnerability can result in complete system compromise, as the attacker can execute arbitrary code with the privileges of the current user. The impact extends beyond simple privilege escalation to potentially enable full system access, data exfiltration, or lateral movement within network environments. This vulnerability represents a significant risk in enterprise environments where Adobe Reader is commonly used for document processing, as it can be triggered through simple document opening operations. The attack vector typically involves delivering a malicious PDF file through social engineering techniques, phishing campaigns, or compromised websites that automatically trigger the vulnerable code path.
Organizations should implement immediate mitigations including prompt patching of affected versions to address this vulnerability. The recommended approach involves upgrading to patched versions of Adobe Acrobat and Reader that contain proper type validation mechanisms. Security administrators should also consider implementing additional protective measures such as PDF sandboxing, restricted user permissions, and network-based filtering to prevent execution of potentially malicious documents. The vulnerability aligns with CWE-466, which describes "Return of Pointer Value Outside of Expected Range," and can be mapped to ATT&CK technique T1203 for "Exploitation for Client Execution" and T1068 for "Exploitation for Privilege Escalation." Organizations should also consider deploying endpoint protection solutions that can detect and block suspicious memory operations associated with type confusion attacks.