Summary
motionEye: Authentication possible via password hash
An authentication bypass vulnerability exists due to improper trust in client-controlled cookies. The application accepts user-supplied cookie values containing a username and password-hash-derived value as sufficient authentication material. These cookies can be set or modified prior to login, allowing an unauthenticated attacker to impersonate arbitrary users without knowledge of the plaintext password. This issue stems from the absence of server-side validation of authentication state and reliance on attacker-controlled cookie data
Details
The vulnerability arises because the application accepts the client-supplied cookies named meye_password_hash and meye_username as sufficient authentication material. The server does not validate these values against a server-side session or enforce proper authentication checks before establishing an authenticated state. As a result, an unauthenticated attacker can set or modify these cookies to impersonate another user if the target username and corresponding hash are known.
These cookies normally appear after using the "switch user" functionality; however, they can be added manually prior to authentication using standard browser tools (e.g., developer tools or cookie editors) or dynamically loaded by submitting blank credentials. When supplied, the server accepts them and authenticates the attacker as the specified user bypassing the intended authentication flow
Additionally, the password-hash value and username for the admin account used by the application is stored in /etc/motioneye/motion.conf which is globally readable by default on the local system. This means any local user with shell access can obtain a valid hash and values and use them to impersonate the admin via the cookie manipulation described above. While local access is required to retrieve the hash, this significantly lowers the barrier to exploitation in multi-user environments.
PoC
Starting state unauthenticated with no cookies:
After manually adding or submitting blank credentials to get the cookies loaded:
Adding the credentials and refreshing the page gives us a valid session:
version information and session interaction validation
Who is impacted?
Any MotionEye deployment where attackers have access to a username and hash, and/or the /etc/motioneye/motion.conf file with the admin username and hash.
Potential consequences:
- Account lockouts
- Attacker persistence by changing the password
- Enumeration of data
- Destruction of data
- Exfiltration of data
Impact
Authentication bypass
The application does not adequately verify the identity of a user, device, or process before granting access. Typical impact: unauthorized access to functions or data reserved for authenticated parties.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is CVE-2026-46488? CVE-2026-46488 is a critical-severity improper authentication vulnerability in motioneye (pip), affecting versions < 0.44.0. It is fixed in 0.44.0. The application does not adequately verify the identity of a user, device, or process before granting access.
- Which versions of motioneye are affected by CVE-2026-46488? motioneye (pip) versions < 0.44.0 is affected.
- Is there a fix for CVE-2026-46488? Yes. CVE-2026-46488 is fixed in 0.44.0. Upgrade to this version or later.
- Is CVE-2026-46488 exploitable, and should I be worried? Whether CVE-2026-46488 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-46488 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-46488? Upgrade
motioneyeto 0.44.0 or later.