CVE-2025-6660: pdf-xchange pdf-tools Heap-based Buffer Overflow

Vulnerability summary

CVE-2025-6660 is a high (CVSS 7.8) Heap-based Buffer Overflow vulnerability in pdf-xchange pdf-tools. EPSS estimates a 0.30% chance of exploitation in the next 30 days, higher than 21.2% of scored vulnerabilities.

Timeline

1. 25-06-2025
   PublishedVulnerability first disclosed.
2. 26-06-2025
   Last modifiedVulnerability information updated.

Description

PDF-XChange Editor GIF File Parsing Heap-based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of PDF-XChange Editor. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the parsing of GIF files. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a fixed-length heap-based buffer. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-26763.

• CWE-122Heap-based Buffer OverflowA heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().