CVE-2025-66507VulnerabilityPublished 9 Dec 2025

CVE-2025-66507: 1Panel · Client-Side Enforcement of Server-Side Security

Affects 1PanelSource CVE Database V5

Not known to be exploited · CVSS 7.5 High : upgrade to 2.0.14 soon.

Data as of 26 Oct 2026, 08:30 UTC

CVSS 3.1 base score

7.5High

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

EPSS: 0.4% chance of exploitation in 30 days – higher than 40% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 2.0.14

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: None
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: 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: None: The vulnerable system can be exploited without any interaction from any user.
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: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 9 Dec 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 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 1panel-dev/1Panel to 2.0.14.

Affected software

Product	Affected	Fixed in
GitHub1panel-dev/1Panel`pkg:github/1panel-dev/1Panel`Other threats	Affected <2.0.14	Fixed in 2.0.14

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

AI-suggested

European organizations using 1Panel should immediately upgrade to version 2.0.14 or later to ensure the vulnerability is patched. Until patching is possible, organizations should implement compensating controls such as restricting access to the 1Panel interface via IP whitelisting or VPNs to limit exposure. Enforce strong, unique passwords and consider multi-factor authentication (MFA) for all accounts to reduce the risk of account takeover. Monitor authentication logs for unusual login attempts or patterns indicative of automated attacks. Additionally, review and harden server-side validation logic to ensure no client-controlled parameters can bypass security controls. Conduct regular security assessments and penetration tests focusing on web management interfaces to detect similar flaws. Finally, educate administrators about the risks of client-side enforcement of security controls and the importance of server-side validation.

Description

1Panel is an open-source, web-based control panel for Linux server management. Versions 2.0.13 and below allow an unauthenticated attacker to disable CAPTCHA verification by abusing a client-controlled parameter. Because the server previously trusted this value without proper validation, CAPTCHA protections can be bypassed, enabling automated login attempts and significantly increasing the risk of account takeover (ATO). This issue is fixed in version 2.0.14.

Impact

For European organizations, this vulnerability poses a significant risk to the confidentiality and integrity of server management accounts. Successful exploitation can lead to unauthorized access to Linux servers managed via 1Panel, potentially allowing attackers to manipulate server configurations, deploy malware, or exfiltrate sensitive data. The bypass of CAPTCHA protections facilitates automated brute-force attacks, increasing the likelihood of account takeover, especially if weak or reused credentials are in use. This can disrupt business operations, compromise customer data, and lead to regulatory non-compliance under GDPR due to unauthorized access incidents. Organizations relying on 1Panel for critical infrastructure management are particularly vulnerable, as attackers gaining control over server management interfaces can escalate attacks within internal networks. The lack of required authentication or user interaction lowers the barrier for exploitation, increasing the threat landscape.

CWE-602Client-Side Enforcement of Server-Side Security (opens in a new tab)
Class weaknessLikelihood of exploit: MediumOWASP Top 10 A06:2025: Insecure Design (opens in a new tab)
The product is composed of a server that relies on the client to implement a mechanism that is intended to protect the server.
Architecture and Design
For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely.
Architecture and Design
If some degree of trust is required between the two entities, then use integrity checking and strong authentication to ensure that the inputs are coming from a trusted source.
OWASP Cheat Sheets
Docker Security (opens in a new tab)
Abuse Case (opens in a new tab)
Deserialization (opens in a new tab)
Access Control (opens in a new tab)
Authorization Testing Automation (opens in a new tab)
OWASP ASVS 4.0.3
V1.4.1 (opens in a new tab)
V1.5.3 (opens in a new tab)
V4.1.1 (opens in a new tab)
Attack patterns
Manipulating Hidden Fields (opens in a new tab)
Create Malicious Client (opens in a new tab)
Removing Important Client Functionality (opens in a new tab)
Removing/short-circuiting 'Purse' logic: removing/mutating 'cash' decrements (opens in a new tab)
Accessing/Intercepting/Modifying HTTP Cookies (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-807Reliance on Untrusted Inputs in a Security Decision (opens in a new tab)
Base weaknessLikelihood of exploit: HighOWASP Top 10 A06:2025: Insecure Design (opens in a new tab)
The product uses a protection mechanism that relies on the existence or values of an input, but the input can be modified by an untrusted actor in a way that bypasses the protection mechanism.
Architecture and Design · Attack Surface Reduction
Store state information and sensitive data on the server side only.
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.
Architecture and Design
For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks…
OWASP Cheat Sheets
Secure Design Principles (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-290Authentication Bypass by Spoofing (opens in a new tab)
Base weaknessOWASP Top 10 A07:2025: Authentication Failures (opens in a new tab)
This attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks.
OWASP Cheat Sheets
REST Security (opens in a new tab)
JSON Web Token for Java (opens in a new tab)
OWASP Authentication (opens in a new tab)
OWASP ASVS 4.0.3
V3.5.1 (opens in a new tab)
V2.8.5 (opens in a new tab)
V2.8.4 (opens in a new tab)
Attack patterns
Creating a Rogue Certification Authority Certificate (opens in a new tab)
Web Services API Signature Forgery Leveraging Hash Function Extension Weakness (opens in a new tab)
Signature Spoof (opens in a new tab)
Signature Spoofing by Misrepresentation (opens in a new tab)
Session Credential Falsification through Prediction (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 16 Dec 2025, 06:03 UTC

WeaknessesCWE-602, CWE-807, CWE-290

Technical details

References

Community reviews

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