Summary
Payload: Client uploads could overwrite S3 objects
Workarounds
Disable client uploads until you can upgrade.
Impact
An authenticated user could overwrite an existing S3 object belonging to another upload collection, bypassing that collection’s access controls and prior file validation.
You are affected if ALL of these are true:
- Client uploads are enabled for multiple collections that share an S3 bucket.
- useCompositePrefixes is not configured or is set to
false.
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.
Already deployed Kodem?
See it in your environmentNew to Kodem? Get a demo →Remediation advice
Users should upgrade Payload packages to >= 3.90.0 or >= 4.0.0-canary.34.
Frequently Asked Questions
- What is CVE-2026-105867? CVE-2026-105867 is a high-severity security vulnerability in @payloadcms/storage-s3 (npm), affecting versions < 3.90.0. It is fixed in 3.90.0, 4.0.0-canary.34.
- Which versions of @payloadcms/storage-s3 are affected by CVE-2026-105867? @payloadcms/storage-s3 (npm) versions < 3.90.0 is affected.
- Is there a fix for CVE-2026-105867? Yes. CVE-2026-105867 is fixed in 3.90.0, 4.0.0-canary.34. Upgrade to this version or later.
- Is CVE-2026-105867 exploitable, and should I be worried? Whether CVE-2026-105867 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-2026-105867 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-2026-105867?
- Upgrade
@payloadcms/storage-s3to 3.90.0 or later - Upgrade
@payloadcms/storage-s3to 4.0.0-canary.34 or later
- Upgrade