CVE-2021-39833 is an out-of-bounds read vulnerability (CWE-125) identified in Adobe FrameMaker versions 2019 Update 8 and earlier, as well as 2020 Release Update 2 and earlier. This vulnerability arises when FrameMaker processes certain TIF image files, allowing an attacker to craft a malicious TIF file that triggers an out-of-bounds read operation. The consequence of this vulnerability is the potential disclosure of sensitive memory contents, which could include sensitive application data or memory layout information. Such information disclosure can aid attackers in bypassing security mitigations like Address Space Layout Randomization (ASLR), thereby facilitating further exploitation such as code execution or privilege escalation. Exploitation requires user interaction, specifically that a victim opens a maliciously crafted TIF file within the vulnerable FrameMaker application. There are no known exploits in the wild reported for this vulnerability as of the publication date. The vulnerability does not have an official CVSS score but is classified as medium severity by the vendor. The lack of a patch link suggests that remediation may require updating to a later, fixed version of FrameMaker or applying vendor-provided patches once available. Given the nature of the vulnerability, it primarily impacts confidentiality by leaking memory contents, with potential indirect impacts on integrity and availability if leveraged in chained attacks.

For European organizations, the impact of CVE-2021-39833 is primarily related to the confidentiality of sensitive information processed or stored in memory by Adobe FrameMaker. Organizations in sectors such as publishing, technical documentation, engineering, and academia that rely on FrameMaker for document creation and management are at risk. Disclosure of memory contents could reveal sensitive intellectual property, internal document structures, or security-related information that could be used to facilitate further attacks. While the vulnerability itself does not directly cause system compromise or denial of service, the ability to bypass ASLR could enable attackers to execute more sophisticated exploits, potentially leading to broader system compromise. The requirement for user interaction (opening a malicious TIF file) means that phishing or social engineering campaigns could be used to deliver the exploit, increasing the risk in environments with less stringent user awareness or email filtering. The absence of known exploits in the wild reduces immediate risk but does not eliminate the threat, especially as attackers may develop exploits over time. Organizations with high-value intellectual property or regulatory requirements for data confidentiality should consider this vulnerability a significant risk.

1. Update Adobe FrameMaker to the latest available version beyond 2019 Update 8 and 2020 Release Update 2, as vendors typically address such vulnerabilities in subsequent releases. 2. Implement strict email and file filtering policies to block or quarantine TIF files from untrusted sources, reducing the likelihood of malicious files reaching end users. 3. Educate users on the risks of opening unsolicited or unexpected image files, especially within FrameMaker or related applications. 4. Employ application whitelisting and sandboxing techniques to limit the ability of FrameMaker to access sensitive system resources or execute arbitrary code. 5. Monitor and audit FrameMaker usage logs for unusual activity, such as unexpected file openings or crashes that could indicate exploitation attempts. 6. Use endpoint detection and response (EDR) tools capable of detecting anomalous memory access patterns or exploitation behaviors related to out-of-bounds reads. 7. If patching is delayed, consider disabling or restricting the use of TIF files within FrameMaker projects where feasible, or convert TIF images to safer formats prior to use. 8. Maintain up-to-date backups of critical documentation to mitigate potential impacts from exploitation attempts that might lead to data corruption or loss.