Security readout for executives and security teams
Plain-English summary
CVE-2026-27567 affects Payload CMS before 3.75.0. A trusted authenticated user with permission to create uploads may abuse external file URL uploads to make the server reach internal network resources. This can expose internal service responses through the application. The issue is patched in 3.75.0, with documented configuration workarounds.
Executive priority
Prioritize remediation for internet-facing or multi-user Payload deployments, especially where less-trusted users can create uploads. This is not currently reported as exploited, but it can expose internal systems reachable from the CMS server.
Technical view
The vulnerability is SSRF in Payload’s external file upload handling, specifically insufficient validation of HTTP redirects. Exposure requires at least one upload-enabled collection and a user with create access to that collection. CVSS is 6.5 with high confidentiality and integrity impact, high privileges required, network attack vector, and no user interaction.
Likely exposure
Likely exposure is limited to Payload instances below 3.75.0 that enable uploads and allow external file uploads. Risk depends heavily on which authenticated users have create access to upload-enabled collections and what internal services the Payload server can reach.
Exploitation context
The source bundle does not indicate known active exploitation, and the CVE is not listed as KEV. Exploitation requires authenticated access with upload collection write permissions. Successful abuse could retrieve response content from internal services through Payload.
Researcher notes
Focus validation on version, upload-enabled collections, external file upload configuration, and create permissions. The advisory identifies redirect validation as the root issue. Avoid assuming exposure where uploads, external file uploads, or required permissions are absent.
Mitigation direction
- Upgrade Payload to version 3.75.0 or later.
- Disable external file uploads using the disableExternalFile upload collection option.
- Restrict create access on upload-enabled collections to trusted users only.
- Review vendor advisory and release notes before production rollout.
Validation and detection
- Inventory Payload deployments and identify versions below 3.75.0.
- Check collections for upload enabled and external file upload availability.
- Review access controls for users with create permission on upload-enabled collections.
- Confirm upgrade to 3.75.0 or confirm documented workarounds are applied.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-918: Information exposure and cloud metadata lookup
Information exposure and SSRF weaknesses can make discovery, cloud metadata, and credential material review relevant. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCloud metadata behavior lookup
The CVE wording references SSRF or metadata access, so cloud discovery and credential material review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupFile access behavior lookup
The CVE wording references file access or upload behavior, so file telemetry and web shell review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-27567 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 6.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N1.25.2Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
6.5MediumVector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/payloadcms/payload/security/advisories/GHSA-hhfx-5x8j-f5f6CVE reference · x_refsource_CONFIRM
- https://github.com/payloadcms/payload/commit/1041bb6CVE reference · x_refsource_MISC
- https://github.com/payloadcms/payload/releases/tag/v3.75.0CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Server-Side Request Forgery (SSRF)
Server-Side Request Forgery (SSRF) represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.