CVE-2023-21593 in InDesign
Summary
by MITRE • 02/18/2023
Adobe InDesign versions ID18.1 (and earlier) and ID17.4 (and earlier) are affected by a NULL Pointer Dereference vulnerability. An unauthenticated attacker could leverage this vulnerability to achieve an application denial-of-service 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 • 09/21/2025
Adobe InDesign versions ID18.1 and earlier as well as ID17.4 and earlier contain a critical NULL Pointer Dereference vulnerability designated as CVE-2023-21593. This vulnerability resides within the application's memory management mechanisms and represents a fundamental flaw in how the software handles pointer references during file processing operations. The vulnerability stems from insufficient input validation and error handling within the document parsing routines that process various file formats including those used in professional publishing workflows. When a malicious file is processed by the vulnerable InDesign application, the software attempts to dereference a null pointer reference, leading to an abrupt application termination and system crash. This type of vulnerability falls under CWE-476 which specifically addresses NULL Pointer Dereference conditions in software implementations. The attack vector requires user interaction as the malicious file must be opened by an unsuspecting user, making this a classic social engineering target that exploits human factors within the security ecosystem. The vulnerability manifests as a denial-of-service condition that affects the current user context, meaning the application crashes but does not provide an opportunity for remote code execution or privilege escalation. However, the operational impact extends beyond simple application instability as it can disrupt creative workflows in professional environments where InDesign is a critical component of publishing pipelines. Organizations relying on InDesign for graphic design and desktop publishing operations face significant risk of productivity loss when this vulnerability is exploited, particularly in scenarios where multiple users work with shared documents or automated publishing systems. The vulnerability aligns with ATT&CK technique T1499.004 which covers network denial of service attacks targeting applications, though in this case the attack occurs through local file manipulation rather than network-based exploitation. From a threat modeling perspective, this vulnerability represents a low-effort attack vector that could be leveraged by adversaries to disrupt business operations, potentially causing cascading effects in production environments where InDesign is integrated with other creative software suites.
The technical implementation of this vulnerability demonstrates poor defensive programming practices where the software fails to validate pointer states before attempting memory access operations. During normal document processing, InDesign's parsing engine encounters malformed or specially crafted data structures that result in null pointer assignments which are then immediately dereferenced without proper null checks. This particular flaw affects the application's ability to gracefully handle corrupted or malicious input files, indicating inadequate error recovery mechanisms within the software's core processing modules. The vulnerability's exploitation requires minimal technical sophistication from attackers, as it simply requires crafting a malicious file that triggers the specific code path leading to the null pointer dereference. Security researchers have identified that the vulnerability occurs in the handling of specific document metadata or embedded content structures that InDesign processes during file opening operations. The absence of proper null pointer validation creates a predictable crash condition that can be reliably reproduced under controlled circumstances, making it an attractive target for adversaries seeking to disrupt user productivity or cause system instability. The vulnerability's impact is limited to local execution context and does not provide a direct path to system compromise, but the denial-of-service nature means that legitimate users cannot access their documents until the application is restarted. This characteristic makes it particularly problematic in collaborative environments where multiple users may be working simultaneously on shared projects. The vulnerability's presence in both major version lines indicates a persistent issue within the software's architecture that has not been adequately addressed through previous patches or updates.
Organizations should prioritize immediate remediation of this vulnerability by updating to Adobe InDesign versions that contain the necessary security patches and fixes. The recommended mitigation strategy involves implementing a comprehensive patch management program that ensures all users have access to the latest security updates from Adobe. System administrators should also consider implementing additional security controls such as application whitelisting to prevent execution of untrusted files, though this approach may impact legitimate workflow processes in creative environments. Network security teams should monitor for unusual file access patterns or attempts to distribute malicious files through internal networks, as this vulnerability could potentially be used as part of broader attack campaigns. The vulnerability's requirement for user interaction means that security awareness training should emphasize the importance of not opening suspicious files from unknown sources, particularly in environments where users may receive files from external collaborators or vendors. Organizations should also implement file validation mechanisms that can identify potentially malicious content before it reaches the InDesign application, reducing the attack surface for this particular vulnerability. Regular security assessments should include testing for similar null pointer dereference conditions in other Adobe Creative Suite applications, as these types of vulnerabilities often occur in software with similar architectural patterns. The vulnerability's classification as a denial-of-service issue means that incident response procedures should include steps for quickly restoring application availability and ensuring that users can continue their creative work without extended downtime. Additionally, organizations should consider the potential business impact of such disruptions and develop contingency plans that allow for continued productivity even when individual applications are compromised.