Craft CMS: Unauthorized Deletion of Source Assets During File Replacement
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- None · Low · Low
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-639.
Summary
Craft CMS is a content management system (CMS). Versions 5.0.0-RC1 through 5.9.20, and 4.0.0-RC1 through 4.17.13 contain an authorization issue in the AssetsController::actionReplaceFile that can delete a source asset without source delete permission by supplying both assetId and sourceAssetId. AssetsController::actionReplaceFile() supports replacing a target asset file using another existing asset as the source. The action loads: assetId -> $assetToReplace and sourceAssetId -> $sourceAsset, then enforces replace permissions using ($assetToReplace ?: $sourceAsset). When both IDs are provided, this expression resolves to the target asset so no permission check is performed against the source asset volume. When both assets are present, Craft copies the source file into the target and then deletes the source asset. There is no deletion check for for the source asset. An authenticated user who can replace files in one volume can delete assets in another volume where they do not have delete permission, as long as they can obtain a sourceAssetId, leading to broken content references and data loss. This issue has been fixed in versions 4.17.14 and 5.9.21.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Craft CMS | cms | 5.0.0-RC1 to before 5.9.21; 4.0.0-RC1 to before 4.17.14 | 5.9.21, 4.17.14 | Patch available | CNA |
| — | craftcms/cms (Packagist) | 5.0.0-RC1 to before 5.9.21 | 5.9.21 | Patch available | GHSA-qh45-9g5p-m2v4 |
| — | craftcms/cms (Packagist) | 4.0.0-RC1 to before 4.17.14 | 4.17.14 | Patch available | GHSA-qh45-9g5p-m2v4 |
- cms VendorCraft CMS Affected 5.0.0-RC1 to before 5.9.21; 4.0.0-RC1 to before 4.17.14 Fixed in 5.9.21, 4.17.14 Patch available CNA
- craftcms/cms (Packagist) Vendor— Affected 5.0.0-RC1 to before 5.9.21 Fixed in 5.9.21 Patch available GHSA-qh45-9g5p-m2v4
- craftcms/cms (Packagist) Vendor— Affected 4.0.0-RC1 to before 4.17.14 Fixed in 4.17.14 Patch available GHSA-qh45-9g5p-m2v4
Remediation
- Fix · CNA cms (craftcms) Fixed in 5.9.21, 4.17.14
- Fix · GHSA-qh45-9g5p-m2v4 craftcms/cms (Packagist) Fixed in 5.9.21 Advisory →
- Fix · GHSA-qh45-9g5p-m2v4 craftcms/cms (Packagist) Fixed in 4.17.14 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-50283
- 2026-10-03 Alias added: GHSA-qh45-9g5p-m2v4
References
More Craft CMS vulnerabilities
- TI-2025-23503 Craft CMS Allows Remote Code Execution KEVCVSS 3.1CRITICAL 10.0
- TI-2024-37138 RCE when PHP `register_argc_argv` config setting is enabled in craftcms/cms KEVCVSS 4.0CRITICAL 9.3
- TI-2025-16994 Potential RCE with a compromised security key in craft/cms KEVCVSS 3.1HIGH 8.1
- TI-2025-24595 Craft CMS stores user-provided content in session files KEVCVSS 4.0MEDIUM 6.9
- TI-2023-22284 Craft CMS Remote Code Execution vulnerability CVSS 3.1CRITICAL 10.0
- TI-2024-25171 Craft CMS up to v3.7.31 was discovered to contain a SQL injection vulnerability via the GraphQL API endpoint. CVSS 3.1CRITICAL 9.8
Sources
- CVE-2026-50283 · CVE Program
- CVE-2026-50283 · NVD
- FIRST EPSS
- GHSA-qh45-9g5p-m2v4 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences