CVE-2025-8838VulnerabilityPublished 11 Aug 2025

CVE-2025-8838: WinterChenS my-site · Improper Authentication

Affects WinterChenS my-siteSource CVE Database V5

Not known to be exploited · CVSS 6.9 Medium.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 4.0 base score

6.9Medium

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

EPSS: 0.5% chance of exploitation in 30 days – higher than 45% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P

Base metrics

Attack Vector: Network
Attack Complexity: Low
Attack Requirements: None
Privileges Required: None
User Interaction: None
Vulnerable system confidentiality: Low
Vulnerable system integrity: Low
Vulnerable system availability: Low
Subsequent system confidentiality: None
Subsequent system integrity: None
Subsequent system availability: None

Threat metrics

Exploit Maturity: POC

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

Attack Vector: Network: The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, 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: The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Attack Requirements: None: The successful attack does not depend on the deployment and execution conditions of the vulnerable system. The attacker can expect to be able to reach the vulnerability and execute the exploit under all or most instances of the vulnerability.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files of the vulnerable system to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without interaction from any human user, other than the attacker.
Vulnerable system 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 Vulnerable System.
Vulnerable system 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 to the Vulnerable System.
Vulnerable system 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 Vulnerable System 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 Vulnerable System.
Subsequent system confidentiality: None: There is no loss of confidentiality within the Subsequent System or all confidentiality impact is constrained to the Vulnerable System.
Subsequent system integrity: None: There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System.
Subsequent system availability: None: There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.
Exploit Maturity: POC: Based on threat intelligence sources each of the following must apply: · Proof-of-concept is publicly available · No knowledge of reported attempts to exploit this vulnerability · No knowledge of publicly available solutions used to simplify attempts to exploit the vulnerability

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 11 Aug 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

AI-suggested

1. Conduct immediate code review and penetration testing focusing on the /admin/preHandle function to verify the existence and exploitability of the authentication bypass. 2. Implement strict input validation and sanitization on the 'uri' parameter to prevent manipulation leading to authentication bypass. 3. Enforce multi-factor authentication (MFA) on all administrative interfaces to add an additional security layer beyond the vulnerable authentication mechanism. 4. Monitor web server logs and application access logs for suspicious access patterns or unauthorized attempts targeting the /admin/ endpoint. 5. If possible, restrict access to the backend interface by IP whitelisting or VPN-only access to reduce exposure. 6. Engage with the vendor or maintainers to obtain official patches or updates and apply them promptly once available. 7. Maintain an up-to-date inventory of affected systems and ensure continuous integration pipelines include security testing for this vulnerability. 8. Prepare incident response plans specific to potential unauthorized backend access to minimize impact if exploitation occurs.

Description

A vulnerability has been found in WinterChenS my-site up to 1f7525f15934d9d6a278de967f6ec9f1757738d8. This vulnerability affects the function preHandle of the file /admin/ of the component Backend Interface. The manipulation of the argument uri leads to improper authentication. The attack can be initiated remotely. The exploit has been disclosed to the public and may be used. The real existence of this vulnerability is still doubted at the moment. This product is using a rolling release to provide continious delivery. Therefore, no version details for affected nor updated releases are available. The code maintainer responded to the issue that "[he] tried it, and using this link automatically redirects to the login page."

Impact

For European organizations using WinterChenS my-site, this vulnerability could lead to unauthorized access to backend administrative interfaces, potentially allowing attackers to manipulate site configurations, access sensitive data, or disrupt service availability. Given the medium severity and partial impact on confidentiality, integrity, and availability, exploitation could result in data leakage, unauthorized changes, or denial of service. However, the uncertainty around exploitability and the lack of known active exploits reduce immediate risk. Organizations relying on this product for critical web services or handling sensitive user data should be cautious, as any successful authentication bypass could undermine trust and compliance with data protection regulations such as GDPR. The continuous delivery model complicates patch management, potentially delaying fixes or making it harder to verify vulnerability status. European entities with public-facing web applications or administrative portals using this software are particularly at risk if the vulnerability is confirmed exploitable.

References

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