GHSA-R3CW-C95M-WFH9
Vulnerability from github – Published: 2026-06-22 20:59 – Updated: 2026-06-22 20:59Summary
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
Impact
Authentication bypass
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
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "motioneye"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.44.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-46488"
],
"database_specific": {
"cwe_ids": [
"CWE-256",
"CWE-287",
"CWE-328",
"CWE-836"
],
"github_reviewed": true,
"github_reviewed_at": "2026-06-22T20:59:31Z",
"nvd_published_at": null,
"severity": "CRITICAL"
},
"details": "### Summary\nAn 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\n\n### Details\nThe 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.\n\nThese 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\n\nAdditionally, 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. \n\n### PoC\nStarting state unauthenticated with no cookies:\n\u003cimg width=\"644\" height=\"475\" alt=\"start state\" src=\"https://github.com/user-attachments/assets/cf4aff78-65f7-4f67-99e2-9134c8f04277\" /\u003e\n\nAfter manually adding or submitting blank credentials to get the cookies loaded:\n\u003cimg width=\"643\" height=\"470\" alt=\"empty cookies\" src=\"https://github.com/user-attachments/assets/223878eb-f085-4ac5-a92a-2ac21831c594\" /\u003e\n\n\nAdding the credentials and refreshing the page gives us a valid session:\n\u003cimg width=\"641\" height=\"466\" alt=\"admin login with hash\" src=\"https://github.com/user-attachments/assets/94b350ef-dd32-4cae-8bd8-e48841873f79\" /\u003e\n\n\nversion information and session interaction validation\n\u003cimg width=\"643\" height=\"468\" alt=\"verison\" src=\"https://github.com/user-attachments/assets/94290ad6-4e82-4026-8e27-5374e2f3a631\" /\u003e\n\n\n### Impact\nAuthentication bypass\n\n### Who is impacted?\n\nAny 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.\n\nPotential consequences:\n\n- Account lockouts \n- Attacker persistence by changing the password\n- Enumeration of data\n- Destruction of data\n- Exfiltration of data",
"id": "GHSA-r3cw-c95m-wfh9",
"modified": "2026-06-22T20:59:31Z",
"published": "2026-06-22T20:59:31Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/motioneye-project/motioneye/security/advisories/GHSA-r3cw-c95m-wfh9"
},
{
"type": "PACKAGE",
"url": "https://github.com/motioneye-project/motioneye"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "motionEye: Authentication possible via password hash"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.