CVE-2025-6660: pdf-tools Heap Overflow — Fix

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.

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CVSS v3.1 Score

7.8

HIGH

CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-122 CWE-122

Affected Products

Vendor	Product	Versions
pdf-xchange	pdf-tools	All
pdf-xchange	pdf-xchange_editor	All
pdf-xchange	pdf-xchange_pro	All

References

Advisories & Patches

https://www.pdf-xchange.com/support/security-bulletins.html

Other References

https://www.zerodayinitiative.com/advisories/ZDI-25-443/

Frequently Asked Questions

What is CVE-2025-6660? +

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. It has a CVSS v3.1 base score of 7.8 (HIGH).

How severe is CVE-2025-6660? +

CVE-2025-6660 has a CVSS v3.1 score of 7.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2025-6660? +

CVE-2025-6660 affects products from pdf-xchange, specifically: pdf-tools, pdf-xchange_editor, pdf-xchange_pro. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-6660? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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