CVE-2025-6656VulnerabilityPublished 25 Jun 2025Updated 30 Jun 2025

CVE-2025-6656: PDF-XChange Editor · Out-of-bounds Read

Affects PDF-XChange EditorSource CVE Database V5

Not known to be exploited · CVSS 3.3 Low.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 3.0 base score

3.3Low

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.2% chance of exploitation in 30 days – higher than 15% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Attack Vector: Local
Attack Complexity: Low
Privileges Required: None
User Interaction: Required
Scope: Unchanged
Confidentiality: Low
Integrity: None
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Local: The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either: the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or remotely (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., tricking a legitimate user into opening a malicious document).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: Required: Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 25 Jun 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
PDF-XChange PDF-XChange Editor	Affected =10.5.2.395	Fixed in–

AI-suggested

To mitigate the risk posed by CVE-2025-6656, European organizations should implement the following specific measures: 1) Restrict or monitor the use of PDF-XChange Editor version 10.5.2.395, prioritizing updates to patched versions once available. 2) Employ advanced email and web filtering solutions to detect and block malicious PDF attachments or links that could trigger the vulnerability. 3) Educate users on the risks of opening unsolicited or suspicious PDF files, emphasizing caution with documents from unknown sources. 4) Utilize endpoint detection and response (EDR) tools to monitor for anomalous behaviors indicative of exploitation attempts, especially those involving memory reads or unusual process activity related to PDF-XChange Editor. 5) Implement strict application whitelisting and privilege restrictions to reduce the impact of potential exploitation chaining this vulnerability with others. 6) Conduct regular threat hunting focused on PDF-based attacks and review logs for signs of information disclosure attempts. These targeted actions go beyond generic advice by focusing on controlling the specific attack vectors and limiting the vulnerability's exploitation potential in operational environments.

Description

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.

Impact

For European organizations, the primary impact of CVE-2025-6656 is the potential leakage of sensitive information from memory when users open malicious PDF files containing crafted PRC data. This could lead to exposure of confidential data such as credentials, personal information, or internal documents. While the vulnerability alone does not allow code execution, its exploitation in conjunction with other vulnerabilities could escalate to full compromise of affected systems. Organizations in sectors handling sensitive or regulated data—such as finance, healthcare, government, and critical infrastructure—may face increased risk if attackers combine this flaw with other exploits. The requirement for user interaction limits the attack surface to scenarios involving phishing or malicious document distribution. However, given the widespread use of PDF-XChange Editor in Europe, especially in professional and governmental environments, the risk of targeted attacks exploiting this vulnerability exists. The low CVSS score suggests limited immediate threat, but the potential for information disclosure and subsequent exploitation warrants attention.

CWE-125Out-of-bounds Read (opens in a new tab)
Base weaknessCWE Top 25 (2025): #8
The product reads data past the end, or before the beginning, of the intended buffer.
Implementation · Input Validation
Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
Architecture and Design · Language Selection
Use a language that provides appropriate memory abstractions.
OWASP Cheat Sheets
XML Security (opens in a new tab)
Mass Assignment (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.1 (opens in a new tab)
V5.1.4 (opens in a new tab)
V5.1.3 (opens in a new tab)
Attack patterns
Overread Buffers (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 25 Jun 2025, 22:19 UTC

WeaknessesCWE-125

Technical details

References

Community reviews

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