CVE-2026-33656:
EspoCRM is an open source customer relationship management application. Prior to version 9.3.4, EspoCRM's built-in formula scripting engine allowing updating attachment's sourceId thus allowing an authenticated admin to overwrite the `sourceId` field on `Attachment` entities. Because `sourceId` is concatenated directly into a file path with no sanitization in `EspoUploadDir::getFilePath()`, an attacker can redirect any file read or write operation to an arbitrary path within the web server's `open_basedir` scope. Version 9.3.4 fixes the issue.
Score
A numerical rating that indicates how dangerous this vulnerability is.
9.1Critical- Published Date:Apr 22, 2026
- CISA KEV Date:*No Data*
- Industries Affected:20
Exploitability
- Score:2.3
- Attack Vector:NETWORK
- Attack Complexity:LOW
- Privileges Required:HIGH
- User Interaction:NONE
- Scope:CHANGED
Impact
- Score:6.0
- Confidentiality Impact:HIGH
- Integrity Impact:HIGH
- Availability Impact:HIGH
Description Preview
EspoCRM is an open source customer relationship management application. Prior to version 9.3.4, EspoCRM's built-in formula scripting engine allowing updating attachment's sourceId thus allowing an authenticated admin to overwrite the `sourceId` field on `Attachment` entities. Because `sourceId` is concatenated directly into a file path with no sanitization in `EspoUploadDir::getFilePath()`, an attacker can redirect any file read or write operation to an arbitrary path within the web server's `open_basedir` scope. Version 9.3.4 fixes the issue.
Industries Affected
Below is a list of industries most commonly impacted or potentially at risk based on intelligence.