The vulnerability CVE-2026-24001 affects the jsdiff JavaScript library, which is widely used for text differencing operations. The core issue lies in the parsePatch method, which, prior to fixed versions (8.0.3, 5.2.2, 4.0.4, and 3.5.1), fails to properly handle patch files whose filename headers contain certain line break characters: carriage return (\r), line separator (\u2028), or paragraph separator (\u2029). When such characters are present, parsePatch enters an infinite loop, causing uncontrolled resource consumption, specifically memory exhaustion, ultimately crashing the process. This vulnerability can be exploited remotely without authentication or user interaction by submitting a crafted patch file to an application that uses jsdiff's parsePatch method on user input. Notably, the attack does not require large payloads, rendering size-based input restrictions ineffective. Furthermore, the applyPatch method is vulnerable if it parses patch strings internally via parsePatch. A secondary issue is a Regular Expression Denial of Service (ReDoS) vulnerability triggered by the same characters in the patch header, causing parsePatch to consume O(n³) time, severely degrading performance. The vulnerability is classified under CWE-400 (Uncontrolled Resource Consumption) and CWE-1333 (Inefficient Regular Expression Complexity). The maintainers have addressed these issues in the specified patched versions. Until upgrading, a practical workaround is to reject patches containing the problematic characters in filename headers. No known exploits are reported in the wild as of publication.

For European organizations, the primary impact of CVE-2026-24001 is the risk of denial-of-service attacks against applications that utilize vulnerable versions of jsdiff to parse patches, especially when user input influences patch filenames. Such DoS attacks can disrupt services, degrade application availability, and potentially cause cascading failures in dependent systems. Organizations relying on automated patch processing, code review tools, or collaborative development platforms that incorporate jsdiff are particularly at risk. The low CVSS score reflects limited impact on confidentiality and integrity, but availability can be significantly affected. Given the ease of exploitation without authentication or user interaction, attackers can remotely trigger service outages. This may affect software development firms, managed service providers, and any enterprise integrating jsdiff in their toolchains. The vulnerability's presence in multiple major jsdiff versions suggests a broad potential attack surface. European entities with high dependency on JavaScript-based development tools or CI/CD pipelines should prioritize mitigation to maintain operational continuity.

European organizations should immediately upgrade jsdiff to versions 8.0.3, 5.2.2, 4.0.4, or 3.5.1 or later, depending on their current version lineage. If upgrading is not immediately feasible, implement input validation to reject any patch files containing the problematic line break characters (\r, \u2028, \u2029) in filename headers before parsing. Additionally, audit all application components that invoke parsePatch or applyPatch with user-supplied data to ensure they do not process untrusted patches. Employ runtime monitoring to detect abnormal memory consumption or CPU spikes indicative of exploitation attempts. Incorporate fuzz testing and static analysis focused on patch parsing routines to identify similar vulnerabilities. Finally, maintain strict access controls and logging around patch submission interfaces to detect and respond to suspicious activities promptly.