CVE-2026-105863: CWE-290: Authentication Bypass by Spoofing in payloadcms payload
Description
PayloadCMS versions from 3.0.0 up to but not including 3.90.0, and certain 4.0.0-canary versions before 4.0.0-canary.34, contain an authentication bypass vulnerability. This flaw arises when a custom field option maps to a reserved authentication claim name, allowing unintended values to be placed in the authentication token issued at login. The issue is resolved in version 3.90.0.
CVSS v4.0
Score 9.2critical
Affected software
payloadcms
payload
pkg:github/payloadcms/payloadRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-105863 is an authentication bypass vulnerability in PayloadCMS, a headless content management system. Specifically, in versions >=3.0.0 <3.90.0 and >=4.0.0-canary.0 <4.0.0-canary.34, a custom field option can be mapped to a reserved authentication claim name. This mapping can cause unintended values to be included in the authentication token issued at login, effectively bypassing intended authentication controls. The vulnerability is fixed in version 3.90.0.
Potential Impact
An attacker could exploit this vulnerability to bypass authentication mechanisms by injecting unintended values into authentication tokens. This could lead to unauthorized access with potentially high privileges, compromising the confidentiality and integrity of the system.
Mitigation Recommendations
Upgrade PayloadCMS to version 3.90.0 or later, where this vulnerability has been fixed. No other mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-10-05T23:06:29.748Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ac52a0a2cdf04f656c7686c
Added to database: 10/06/2026, 17:04:10 UTC
Last enriched: 10/06/2026, 17:18:22 UTC
Last updated: 10/06/2026, 18:57:28 UTC
Views: 12
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