Vulnerability-Lookup

CVE-2026-32639 (GCVE-0-2026-32639)

Vulnerability from cvelistv5 – Published: 2026-08-26 17:50 – Updated: 2026-08-29 02:46

Title

Winter: Broken access control in `Cms\Controllers\Index` allows cross-template actions and unauthorized asset uploads

Summary

Winter CMS is a content management system built on the Laravel PHP framework. In versions up to and including 1.2.12, the CMS section's Theme Editor AJAX handlers did not enforce per-template-type permission checks, allowing a backend user with any single CMS permission to act on template types outside their authorized scope. The CMS controller gated access to the section as a whole using OR-logic across its five permissions, but individual handlers such as onSave(), onDelete(), and onDeleteTemplates() did not verify that the user held the specific permission for the requested template type, so a user with only cms.manage_pages could craft AJAX requests to delete layouts, modify partials, or read content files. Separately, the AssetList widget was registered for any user who passed the controller gate regardless of the cms.manage_assets permission, and its onUpload() handler omitted the theme-validation call present on the other mutating handlers, permitting unauthorized file uploads into the active theme's asset directory. Exploitation requires an authenticated backend account holding at least one of the CMS Theme Editor permissions. This issue is fixed in version 1.2.13.

Severity

6.8 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-29 02:46 UTC

CWE

CWE-289 - Authentication Bypass by Alternate Name

Assigner

GitHub_M mitre root

References

4 references

URL	Tags
https://github.com/wintercms/winter/security/advi…	x_refsource_CONFIRM
https://github.com/wintercms/winter/commit/164c62…	x_refsource_MISC
https://github.com/wintercms/winter/commit/5391af…	x_refsource_MISC
https://github.com/wintercms/winter/releases/tag/…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version	CPE status
wintercms	winter	Affected: < 1.2.13	guessed

Show details on NVD website

JSON

To clipboard

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                "id": "CVE-2026-32639",
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FKIE_CVE-2026-32639

Vulnerability from fkie_nvd - Published: 2026-08-26 18:16 - Updated: 2026-08-29 03:17

Severity

6.8 (Medium) - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N

Summary

References

	URL	Tags
	security-advisories@github.com	https://github.com/wintercms/winter/commit/164c62524e8abc153d09c6c35916278bdb746a2b
	security-advisories@github.com	https://github.com/wintercms/winter/commit/5391afa242eba3c476869035b7492e50a262c46b
	security-advisories@github.com	https://github.com/wintercms/winter/releases/tag/v1.2.13
	security-advisories@github.com	https://github.com/wintercms/winter/security/advisories/GHSA-5c4f-9pq9-6c77

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "winter",
          "vendor": "wintercms",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.2.13"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Winter CMS is a content management system built on the Laravel PHP framework. In versions up to and including 1.2.12, the CMS section\u0027s Theme Editor AJAX handlers did not enforce per-template-type permission checks, allowing a backend user with any single CMS permission to act on template types outside their authorized scope. The CMS controller gated access to the section as a whole using OR-logic across its five permissions, but individual handlers such as onSave(), onDelete(), and onDeleteTemplates() did not verify that the user held the specific permission for the requested template type, so a user with only cms.manage_pages could craft AJAX requests to delete layouts, modify partials, or read content files. Separately, the AssetList widget was registered for any user who passed the controller gate regardless of the cms.manage_assets permission, and its onUpload() handler omitted the theme-validation call present on the other mutating handlers, permitting unauthorized file uploads into the active theme\u0027s asset directory. Exploitation requires an authenticated backend account holding at least one of the CMS Theme Editor permissions. This issue is fixed in version 1.2.13."
    }
  ],
  "id": "CVE-2026-32639",
  "lastModified": "2026-08-29T03:17:05.123",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
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          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "HIGH",
          "scope": "CHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N",
          "version": "3.1"
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        "impactScore": 4.0,
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        "type": "Secondary"
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  "published": "2026-08-26T18:16:30.427",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/wintercms/winter/commit/164c62524e8abc153d09c6c35916278bdb746a2b"
    },
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      "url": "https://github.com/wintercms/winter/releases/tag/v1.2.13"
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GHSA-5C4F-9PQ9-6C77

Vulnerability from github – Published: 2026-08-12 15:14 – Updated: 2026-08-12 15:14

Summary

Winter: Broken access control in `Cms\Controllers\Index` allows cross-template actions and unauthorized asset uploads

Details

Impact

Affected versions of Winter CMS did not enforce per-template-type permission checks in the CMS section's AJAX handlers. The CMS controller (Cms\Controllers\Index) used OR-logic across its five permissions (cms.manage_pages, cms.manage_partials, cms.manage_layouts, cms.manage_content, cms.manage_assets) to control access to the section as a whole, but individual handlers such as onSave(), onDelete(), and onDeleteTemplates() did not verify that the authenticated user holds the specific permission corresponding to the requested template type.

This allowed a backend user with any single Theme Editor permission (e.g. cms.manage_pages) to craft AJAX requests targeting template types outside their authorized scope — for example, deleting layouts, modifying partials, or reading content files.

In addition, the AssetList widget was registered for all users who passed the controller gate regardless of whether they held the cms.manage_assets permission, and its onUpload() handler was missing the validateRequestTheme() call that is present on all other mutating handlers in the same widget. This allowed unauthorized file uploads into the active theme's asset directory.

To actively exploit this security issue, an attacker would need access to the Backend with a user account with any of the following permissions:

cms.manage_pages
cms.manage_partials
cms.manage_layouts
cms.manage_content
cms.manage_assets

The Winter CMS maintainers strongly recommend that all Winter CMS sites that rely on granular CMS permission assignments (specifically users with only access to cms.manage_content to only be able to edit content files through the Theme Editor) to update immediately.

Patches

Per-template-type permission checks are now enforced on all Theme Editor AJAX handlers, the AssetList widget is only registered for users with the cms.manage_assets permission, and onUpload() now includes theme validation consistent with the other mutating handlers.

This security issue has been fixed as of v1.2.13.

Workarounds

If users cannot upgrade, they may apply the following changes to their Winter CMS installation manually to resolve this issue:

In modules/cms/controllers/Index.php, wrap each widget registration in the constructor with the corresponding hasAccess() check, and add a validateRequestType() call to the index_onOpenTemplate(), onSave(), onCreateTemplate(), onDeleteTemplates(), onDelete(), onCommit(), and onReset() handlers that verifies the user holds the permission for the requested template type.
In modules/cms/widgets/AssetList.php, add a $this->validateRequestTheme() call at the top of the onUpload() method.

Severity

6.8 (Medium)


                  
                    CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 1.2.12"
      },
      "package": {
        "ecosystem": "Packagist",
        "name": "winter/wn-cms-module"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.2.13"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-32639"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-280"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-08-12T15:14:47Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "### Impact\n\nAffected versions of Winter CMS did not enforce per-template-type permission checks in the CMS section\u0027s AJAX handlers. The CMS controller (`Cms\\Controllers\\Index`) used OR-logic across its five permissions (`cms.manage_pages`, `cms.manage_partials`, `cms.manage_layouts`, `cms.manage_content`, `cms.manage_assets`) to control access to the section as a whole, but individual handlers such as `onSave()`, `onDelete()`, and `onDeleteTemplates()` did not verify that the authenticated user holds the specific permission corresponding to the requested template type.\n\nThis allowed a backend user with any single Theme Editor permission (e.g. `cms.manage_pages`) to craft AJAX requests targeting template types outside their authorized scope \u2014 for example, deleting layouts, modifying partials, or reading content files.\n\nIn addition, the `AssetList` widget was registered for all users who passed the controller gate regardless of whether they held the `cms.manage_assets` permission, and its `onUpload()` handler was missing the `validateRequestTheme()` call that is present on all other mutating handlers in the same widget. This allowed unauthorized file uploads into the active theme\u0027s asset directory.\n\nTo actively exploit this security issue, an attacker would need access to the Backend with a user account with any of the following permissions:\n\n- `cms.manage_pages`\n- `cms.manage_partials`\n- `cms.manage_layouts`\n- `cms.manage_content`\n- `cms.manage_assets`\n\nThe Winter CMS maintainers strongly recommend that all Winter CMS sites that rely on granular CMS permission assignments (specifically users with only access to `cms.manage_content` to only be able to edit content files through the Theme Editor) to update immediately.\n\n### Patches\n\nPer-template-type permission checks are now enforced on all Theme Editor AJAX handlers, the `AssetList` widget is only registered for users with the `cms.manage_assets` permission, and `onUpload()` now includes theme validation consistent with the other mutating handlers.\n\nThis security issue has been fixed as of v1.2.13.\n\n### Workarounds\n\nIf users cannot upgrade, they may apply the following changes to their Winter CMS installation manually to resolve this issue:\n\n1. In `modules/cms/controllers/Index.php`, wrap each widget registration in the constructor with the corresponding `hasAccess()` check, and add a `validateRequestType()` call to the `index_onOpenTemplate()`, `onSave()`, `onCreateTemplate()`, `onDeleteTemplates()`, `onDelete()`, `onCommit()`, and `onReset()` handlers that verifies the user holds the permission for the requested template type.\n2. In `modules/cms/widgets/AssetList.php`, add a `$this-\u003evalidateRequestTheme()` call at the top of the `onUpload()` method.",
  "id": "GHSA-5c4f-9pq9-6c77",
  "modified": "2026-08-12T15:14:47Z",
  "published": "2026-08-12T15:14:47Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/wintercms/winter/security/advisories/GHSA-5c4f-9pq9-6c77"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/wintercms/winter"
    },
    {
      "type": "WEB",
      "url": "https://github.com/wintercms/winter/releases/tag/v1.2.13"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Winter: Broken access control in `Cms\\Controllers\\Index` allows cross-template actions and unauthorized asset uploads"
}

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.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

CVE-2026-32639 (GCVE-0-2026-32639)

FKIE_CVE-2026-32639

GHSA-5C4F-9PQ9-6C77

Impact

Patches

Workarounds

Tags

Sightings

Nomenclature