VulnerabilityPublished 17 Nov 2025

CVE-2025-63917: PDFPatcher · XML External Entity (XXE)

Affects PDFPatcherSource CVE Database V5

Not known to be exploited · CVSS 7.1 High.

Data as of 26 Oct 2026, 17:16 UTC

CVSS 3.1 base score

7.1High

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

EPSS: 0.4% chance of exploitation in 30 days – higher than 36% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:L

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

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

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
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: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 17 Nov 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 26 Oct 2026.

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 or the CVSS exploit maturity 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
GitHubwmjordan/PDFPatcher`pkg:github/wmjordan/PDFPatcher`Other threats	Affected <=1.1.3.4663	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Immediate mitigation steps include disabling external entity resolution in the XML parser used by PDFPatcher. For .NET applications, this involves configuring XmlReaderSettings or XmlDocument to prohibit DTD processing and external entity resolution. Organizations should audit their use of PDFPatcher and restrict the import of XML bookmarks to trusted sources only. Employing network-level controls to block outbound HTTP requests to untrusted domains can limit data exfiltration via OOB channels. Monitoring and alerting on unusual outbound traffic patterns can help detect exploitation attempts. Until an official patch is released, consider isolating PDFPatcher usage to segmented environments with limited access to sensitive data and internal networks. User education to recognize suspicious files and avoid importing untrusted XML bookmarks is critical. Finally, maintain up-to-date backups and incident response plans to quickly recover from potential denial of service or data breaches.

Description

PDFPatcher thru 1.1.3.4663 executable's XML bookmark import functionality does not restrict XML external entity (XXE) references. The application uses .NET's XmlDocument class without disabling external entity resolution, enabling attackers to: Read arbitrary files from the victim's filesystem, exfiltrate sensitive data via out-of-band (OOB) HTTP requests, perform SSRF attacks against internal network resources, or cause a denial of service via entity expansion attacks.

Impact

For European organizations, the impact of CVE-2025-63917 can be substantial, particularly in sectors such as finance, legal, government, and healthcare where PDF documents often contain sensitive or confidential information. Exploitation could lead to unauthorized disclosure of sensitive files, potentially violating data protection regulations like GDPR. SSRF capabilities could allow attackers to pivot into internal networks, accessing otherwise protected resources, increasing the risk of lateral movement and further compromise. Denial of service attacks could disrupt business operations reliant on PDFPatcher for document workflows. Since the vulnerability requires user interaction, phishing or social engineering campaigns could be used to trick employees into importing malicious XML files, increasing the attack surface. The lack of known exploits in the wild currently reduces immediate risk but does not eliminate the threat, especially as proof-of-concept exploits may emerge. The high confidentiality impact combined with the potential for internal network compromise makes this vulnerability a serious concern for European enterprises.

CWE-611Improper Restriction of XML External Entity Reference (opens in a new tab)
Base weaknessOWASP Top 10 A02:2025: Security Misconfiguration (opens in a new tab)
The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output.
Implementation · System Configuration
Many XML parsers and validators can be configured to disable external entity expansion.
OWASP Cheat Sheets
Deserialization (opens in a new tab)
XML Security (opens in a new tab)
XML External Entity Prevention (opens in a new tab)
OWASP ASVS 4.0.3
V5.5.2 (opens in a new tab)
Attack patterns
Data Serialization External Entities Blowup (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 24 Nov 2025, 17:37 UTC

WeaknessesCWE-611

Technical details

References

Community reviews

Related threats