CVE-2021-21056 in Framemaker
Summary
by MITRE • 03/13/2021
Adobe Framemaker version 2020.0.1 (and earlier) is affected by an Out-of-bounds Read vulnerability when parsing a specially crafted file. An unauthenticated attacker could leverage this vulnerability to achieve arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.
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Analysis
by VulDB Data Team • 04/01/2021
Adobe Framemaker version 2020.0.1 and earlier versions contain a critical out-of-bounds read vulnerability classified as CVE-2021-21056 that stems from insufficient input validation during file parsing operations. This vulnerability resides within the application's handling of specially crafted malformed files that trigger memory access violations when the software attempts to read data beyond allocated buffer boundaries. The flaw represents a classic software security weakness that allows attackers to manipulate memory access patterns and potentially execute arbitrary code with the privileges of the currently logged-in user.
The technical implementation of this vulnerability occurs during the parsing phase of document processing where Framemaker fails to properly validate the length and structure of incoming file data before attempting to read from memory locations. This type of out-of-bounds read vulnerability falls under the CWE-125 weakness category, which specifically addresses out-of-bounds read conditions that can lead to information disclosure, application crashes, or more severe remote code execution scenarios. The vulnerability is particularly dangerous because it requires only a single user interaction through file opening, making it highly exploitable in targeted attack scenarios where social engineering can be employed to convince victims to open malicious documents.
From an operational impact perspective, this vulnerability creates significant risk for organizations that rely heavily on Adobe Framemaker for document creation and editing tasks. The requirement for user interaction makes it less likely to be exploited at scale through automated means, but it remains a serious threat in targeted attacks where attackers can craft convincing social engineering campaigns. The privilege escalation aspect means that successful exploitation could result in complete system compromise, as the code execution occurs within the context of the current user account. This vulnerability aligns with ATT&CK technique T1059.007 for command and scripting interpreter and T1203 for Exploitation for Client Execution, demonstrating how the initial exploitation can lead to broader system compromise.
Organizations should prioritize immediate patch management to address this vulnerability, as Adobe has released security updates to resolve the out-of-bounds read issue. The recommended mitigation strategy involves applying the latest security patches from Adobe while implementing additional protective measures such as restricting user permissions, enabling application whitelisting, and monitoring for suspicious file access patterns. Network-based detection measures should focus on identifying malformed Framemaker files or suspicious file opening activities that could indicate exploitation attempts. Security teams should also consider implementing sandboxing mechanisms for document processing and establishing user education programs to reduce the risk of social engineering attacks targeting this vulnerability. The vulnerability demonstrates the critical importance of input validation and proper memory management in preventing remote code execution exploits that can have devastating consequences for enterprise security postures.