PDF-XChange Editor PRC File Parsing Out-Of-Bounds Read Information Disclosure Vulnerability. This vulnerability allows remote attackers to disclose sensitive information 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 PRC files. The issue results from the lack of proper validation of user-supplied data, which can result in a read past the end of an allocated object. An attacker can leverage this in conjunction with other vulnerabilities to execute arbitrary code in the context of the current process. Was ZDI-CAN-26731.
Conclusion & alert: CVE-2025-6656 is rated Low Risk (17.2/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.21%). Mandatory action: Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-15 | 0.12% | 0.21% | +0.09% |
| 2 | 2026-04-21 | 0.02% | 0.12% | +0.09% |
| 3 | 2025-11-21 | — | 0.02% | — |
Full EPSS history (5 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 3.3 | 3.0 | LOW |
|
1.8 | 1.4 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| pdf-xchange | pdf-tools | 10.5.2.395 | cpe:2.3:a:pdf-xchange:pdf-tools:10.5.2.395:*:*:*:*:*:*:* |
| pdf-xchange | pdf-xchange_editor | 10.5.2.395 | cpe:2.3:a:pdf-xchange:pdf-xchange_editor:10.5.2.395:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://www.pdf-xchange.com/support/security-bulletins.html | Vendor Advisory |
| https://www.zerodayinitiative.com/advisories/ZDI-25-441/ | Third Party Advisory |