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.
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
- Base score: 9.1
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.60%
- Percentile among all scored CVEs: 47
- Score date: 10/5/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
🎯 ATT&CK techniques
How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.
- Exploitation
T1210Exploitation of Remote Serviceslateral movement85 % - Primary impact
T1005Data from Local Systemcollection90 % - Secondary impact
T1083File and Directory Discoverydiscovery70 % - Secondary impact
T1565Data Manipulationimpact75 %
Vulnerabilidad en EspoCRM que requiere autenticación de administrador (PR:H) y acceso de red para manipular sourceId y redirigir operaciones de lectura/escritura de archivos dentro del open_basedir. Permite lectura de datos (T1005), manipulación de archivos (T1565) y enumeración de directorios (T108
Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.
🛡️ ATT&CK mitigations that cover these techniques
Affected technologies (1)
CWEs
- CWE-22
References
Raw JSON (NVD)
Show
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