CVE-2026-55369

Waline login accepts a non-string email as a match-all MongoDB query

Published Oct 28, 2026 CVSS 3.1 · 6.5 Medium EPSS < 1% KEV · Not listed
Description
Waline is a comment system with backend support. Prior to version 1.41.1, the login endpoint POST /api/token reads the email field from the request body without checking its type and passes it straight into the MongoDB storage query. When email is not a string (for example a JSON object such as {"$ne": null}), the MongoDB storage adapter's parseWhere silently DROPS the field rather than rejecting the request, producing an empty filter that matches ALL users. The endpoint then verifies the submitted password against the FIRST user returned (user[0]), which in Waline is the first-registered user — the site administrator. This is a PARTIAL authentication bypass, not a full one. The attacker still needs a valid password for that first user; this is not a zero-knowledge bypass and it does not disclose passwords. Its concrete effects are: (1) the email/identifier factor is removed for the administrator account, (2) user enumeration (a non-string email never fails the "no such user" branch), and (3) credential-stuffing amplification — an attacker can test a leaked or weak password against the administrator account without knowing the administrator's email. This issue has been patched in version 1.41.1.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

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History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Waline
Waline waline
Vendors & Products Waline
Waline waline
Type Values Removed Values Added
Description Waline is a comment system with backend support. Prior to version 1.41.1, the login endpoint POST /api/token reads the email field from the request body without checking its type and passes it straight into the MongoDB storage query. When email is not a string (for example a JSON object such as {"$ne": null}), the MongoDB storage adapter's parseWhere silently DROPS the field rather than rejecting the request, producing an empty filter that matches ALL users. The endpoint then verifies the submitted password against the FIRST user returned (user[0]), which in Waline is the first-registered user — the site administrator. This is a PARTIAL authentication bypass, not a full one. The attacker still needs a valid password for that first user; this is not a zero-knowledge bypass and it does not disclose passwords. Its concrete effects are: (1) the email/identifier factor is removed for the administrator account, (2) user enumeration (a non-string email never fails the "no such user" branch), and (3) credential-stuffing amplification — an attacker can test a leaked or weak password against the administrator account without knowing the administrator's email. This issue has been patched in version 1.41.1.
Title Waline login accepts a non-string email as a match-all MongoDB query
Weaknesses CWE-287
CWE-943
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Nov 2, 2026, 8:14 PM
Reserved
Jun 16, 2026, 6:57 PM
Status
Deferred
Published
Oct 28, 2026, 1:17 PM
Modified
Nov 2, 2026, 9:17 PM