VulnerabilityPublished 27 Oct 2025

CVE-2025-62523: THM-Health PILOS · Permissive Cross-domain Policy with Untrusted Domains

Affects THM-Health PILOSSource CVE Database V5

Not known to be exploited · CVSS 6.3 Medium : upgrade to 4.8.0 when convenient.

Data as of 26 Oct 2026, 14:05 UTC

CVSS 3.1 base score

6.3Medium

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 4.8.0

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

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

Upgrade thm-health/PILOS to 4.8.0.

Affected software

Product	Affected	Fixed in
GitHubthm-health/PILOS`pkg:github/thm-health/PILOS`Other threats	Affected <4.8.0	Fixed in 4.8.0

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

AI-suggested

European organizations should upgrade PILOS to version 4.8.0 or later, where the CORS misconfiguration is patched. Until the upgrade is applied, administrators should review and restrict CORS policies to explicitly whitelist trusted domains rather than reflecting the Origin header dynamically. Disable Access-Control-Allow-Credentials unless absolutely necessary, and ensure that session-origin checks in Laravel are correctly configured and enforced. Conduct security audits to verify no additional vulnerabilities exist that could bypass Laravel’s protections. Implement Content Security Policy (CSP) headers to limit the origins allowed to interact with the application. Monitor network traffic for unusual cross-origin requests and user activity that could indicate exploitation attempts. Educate users about phishing and malicious websites that might attempt to exploit this vulnerability. Regularly update and patch all components of the BigBlueButton and PILOS stack to maintain security posture.

Description

PILOS (Platform for Interactive Live-Online Seminars) is a frontend for BigBlueButton. PILOS before 4.8.0 includes a Cross-Origin Resource Sharing (CORS) misconfiguration in its middleware: it reflects the Origin request header back in the Access-Control-Allow-Origin response header without proper validation or a whitelist, while Access-Control-Allow-Credentials is set to true. This behavior could allow a malicious website on a different origin to send requests (including credentials) to the PILOS API. This may enable exfiltration or actions using the victim’s credentials if the server accepts those cross-origin requests as authenticated. Laravel’s session handling applies additional origin checks such that cross-origin requests are not authenticated by default. Because of these session-origin protections, and in the absence of any other unknown vulnerabilities that would bypass Laravel’s origin/session checks, this reflected-Origin CORS misconfiguration is not believed to be exploitable in typical PILOS deployments. This vulnerability has been patched in PILOS in v4.8.0

Impact

For European organizations using PILOS versions prior to 4.8.0, this vulnerability could potentially allow attackers to perform cross-origin requests that include user credentials, leading to unauthorized actions or data leakage. The impact is mitigated by Laravel’s session-origin protections, but if these are misconfigured or bypassed, sensitive information could be exposed or manipulated. This risk is particularly relevant for organizations conducting live online seminars or remote training sessions, where PILOS is deployed as a frontend for BigBlueButton. Confidentiality and integrity of user sessions could be compromised, potentially affecting personal data or organizational information. Availability impact is limited but possible if unauthorized actions disrupt service. The medium severity rating suggests a moderate risk that should be addressed promptly to prevent exploitation. The lack of known exploits reduces immediate risk but does not eliminate the need for remediation.

CWE-942Permissive Cross-domain Security Policy with Untrusted Domains (opens in a new tab)
Variant weaknessOWASP Top 10 A02:2025: Security Misconfiguration (opens in a new tab)
The product uses a web-client protection mechanism such as a Content Security Policy (CSP) or cross-domain policy file, but the policy includes untrusted domains with which the web client is allowed to communicate.
Architecture and Design · Operation · Attack Surface Reduction
Define a restrictive Content Security Policy or cross-domain policy file.
Architecture and Design · Operation · Attack Surface Reduction
Avoid using wildcards in the CSP / cross-domain policy file. Any domain matching the wildcard expression will be implicitly trusted, and can perform two-way interaction with the target server.
Architecture and Design · Operation · Environment Hardening
For Flash, modify crossdomain.xml to use meta-policy options such as 'master-only' or 'none' to reduce the possibility of an attacker planting extraneous cross-domain policy files on a server.
OWASP ASVS 4.0.3
V8.3.8 (opens in a new tab)
V1.14.1 (opens in a new tab)
V13.4.2 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 27 Oct 2025, 20:38 UTC

WeaknessesCWE-942

Technical details

References

Community reviews

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