CVE-2026-54081 in parser
Summary
by MITRE • 07/29/2026
veraPDF PDF parser is a PDF parser for veraPDF. Prior to 1.30.2 and 1.31.23, veraPDF-parser contains a denial-of-service vulnerability in veraPDF-parser/src/main/java/org/verapdf/pd/font/type1/Type1FontProgram.java and veraPDF-parser/src/main/java/org/verapdf/parser/postscript/PSOperator.java, where a crafted Type 1 font /FontDescriptor /FontFile program can execute unbounded PostScript array allocation, a zero-increment for loop, or self-recursive toExecute user dictionary lookups and exhaust validator memory, CPU, or stack. This issue is fixed in versions 1.30.2 and 1.31.23.
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Analysis
by VulDB Data Team • 07/29/2026
The veraPDF PDF parser vulnerability represents a critical denial-of-service weakness that affects multiple versions of the software library used for PDF validation and processing. This flaw exists within the Type1FontProgram.java and PSOperator.java components of the parser, specifically targeting how the system handles Type 1 font programs and PostScript operations during PDF document validation. The vulnerability stems from insufficient input validation and memory management when processing crafted malicious font descriptors that contain specially constructed PostScript code sequences. Attackers can exploit this weakness by creating PDF documents with malformed Type 1 fonts that trigger unbounded resource consumption during parsing operations.
The technical implementation of this vulnerability involves three primary attack vectors that can individually or collectively exhaust system resources. First, the parser executes unbounded PostScript array allocation operations that can consume unlimited memory as the font program processes nested or recursive array constructions. Second, zero-increment for loops within the PostScript execution environment cause infinite iterations that consume CPU cycles without advancing program execution. Third, self-recursive toExecute user dictionary lookups create stack overflow conditions that exhaust available call stack space. These mechanisms operate at the parser level where font programs are processed, making them particularly dangerous as they can be triggered during routine PDF validation operations. The vulnerability aligns with CWE-400 (Uncontrolled Resource Consumption) and CWE-674 (Uncontrolled Recursion) classifications, while also mapping to ATT&CK technique T1499.004 (Endpoint Denial of Service) in the context of resource exhaustion attacks.
The operational impact of this vulnerability extends beyond simple service disruption to potentially compromise entire validation workflows that depend on veraPDF parser functionality. Organizations relying on automated PDF validation systems for document processing, compliance checking, or content analysis could experience complete system unavailability when encountering maliciously crafted PDF documents. The vulnerability affects both the memory heap and CPU utilization simultaneously, making it particularly challenging to detect and mitigate in real-time processing environments. Network-based applications that accept PDF uploads from untrusted sources become especially vulnerable, as attackers can craft documents that trigger resource exhaustion during validation without requiring any special privileges or authentication. The computational overhead from these attacks can cause cascading failures in document processing pipelines, leading to extended downtime and potential data loss scenarios.
Mitigation strategies for this vulnerability require immediate patching of affected veraPDF versions to 1.30.2 or 1.31.23 where the memory management and PostScript execution controls have been properly implemented. Organizations should implement input validation measures that limit array sizes and recursion depths during PDF processing, particularly for font-related data structures. Network segmentation and sandboxing of PDF validation services can help contain the impact of successful exploitation attempts. Additionally, monitoring systems should be deployed to detect unusual memory consumption patterns or CPU utilization spikes that may indicate exploitation attempts. The fix addresses the core issue by implementing proper bounds checking on PostScript array allocations, introducing loop counter limits for iterative constructs, and adding recursion depth monitoring for dictionary lookups. Security teams should also consider implementing automated patch management processes to ensure rapid deployment of security updates across all systems utilizing veraPDF parser components.