CVE-2025-50055VulnerabilityPublished 27 Oct 2025Updated 30 Oct 2025

CVE-2025-50055: OpenVPN Access Server · Cross-site Scripting

Affects OpenVPN Access ServerSource CVE Database V5

Not known to be exploited · CVSS 6.4 Medium.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 3.1 base score

6.4Medium

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 11% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

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

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: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Changed: An exploited vulnerability can affect resources beyond the security scope managed by the security authority of the vulnerable component. In this case, the vulnerable component and the impacted component are different and managed by different security authorities.
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: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on 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 27 Oct 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 2026-10-26.

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
OpenVPN Access Server	Affected =2.14.0 =2.14.1 =2.14.2 =2.14.3	Fixed in–

AI-suggested

1. Immediately review and restrict the configuration of SAML Assertion Consumer Service (ACS) endpoints to only trusted and verified sources to minimize the risk of malicious RelayState injection. 2. Implement strict input validation and output encoding on the RelayState parameter within the OpenVPN Access Server web interface to neutralize potentially malicious scripts. 3. Monitor OpenVPN Access Server logs for unusual or unexpected RelayState parameter values that could indicate exploitation attempts. 4. Where possible, disable SAML authentication temporarily or switch to alternative authentication methods until a patch is released. 5. Employ web application firewalls (WAFs) with custom rules to detect and block suspicious payloads targeting the RelayState parameter. 6. Keep OpenVPN Access Server updated and subscribe to vendor advisories for prompt application of security patches once available. 7. Educate administrators and users about the risks of XSS and encourage the use of multi-factor authentication to reduce the impact of potential session hijacking. 8. Conduct regular security assessments and penetration testing focusing on the VPN infrastructure and authentication mechanisms to identify and remediate similar vulnerabilities proactively.

Description

Cross-site scripting (XSS) vulnerability in the SAML Authentication module in OpenVPN Access Server version 2.14.0 through 2.14.3 allows configured remote SAML Assertion Consumer Service (ACS) endpoint servers to inject arbitrary web script or HTML via the RelayState parameter

Impact

For European organizations, this vulnerability poses a risk to the confidentiality and integrity of remote access sessions managed via OpenVPN Access Server with SAML authentication enabled. Exploitation could allow attackers to execute malicious scripts in the context of the administrative or user web interface, potentially leading to session hijacking, theft of authentication tokens, or unauthorized actions within the VPN management console. This could result in unauthorized access to internal networks, data exfiltration, or lateral movement within enterprise environments. Given the widespread use of OpenVPN in European enterprises, government agencies, and critical infrastructure sectors, the impact could be significant, especially where SAML-based single sign-on is integrated for user authentication. The vulnerability does not directly affect availability but can indirectly disrupt operations if attackers gain control over VPN access. The absence of known exploits reduces immediate risk but does not eliminate the threat, as attackers may develop exploits once the vulnerability details are public. Organizations relying on OpenVPN Access Server for secure remote access should consider this vulnerability a medium risk that requires timely attention to prevent potential compromise.

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #1OWASP Top 10 A05:2025: Injection (opens in a new tab)
The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.
Architecture and Design · Libraries or Frameworks
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Implementation · Architecture and Design
Understand the context in which your data will be used and the encoding that will be expected. This is especially important when transmitting data between different components, or when generating outputs that can contain multiple encodings at the same time, such as web pages or multi-part mail messages.
Architecture and Design · Implementation · Attack Surface Reduction
Understand all the potential areas where untrusted inputs can enter your software: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide…
OWASP Cheat Sheets
Cross Site Scripting Prevention (opens in a new tab)
DOM based XSS Prevention (opens in a new tab)
Injection Prevention (opens in a new tab)
Abuse Case (opens in a new tab)
Deserialization (opens in a new tab)
OWASP ASVS 4.0.3
V5.3.3 (opens in a new tab)
V1.5.1 (opens in a new tab)
Attack patterns
XSS Using MIME Type Mismatch (opens in a new tab)
DOM-Based XSS (opens in a new tab)
Reflected XSS (opens in a new tab)
Stored XSS (opens in a new tab)
Cross-Site Scripting (XSS) (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

openvpn.net/as-docs/as-3-0-release-notes.html (opens in a new tab)

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 3 Nov 2025, 14:55 UTC

WeaknessesCWE-79

Technical details

References

Community reviews

Related threats