Server-Side Request Forgery in EspoCRM by Espo Technologies
CVE-2026-33534

4.3MEDIUM

Key Information:

Vendor

Espocrm

Status
Espocrm
Vendor
CVE Published:
13 April 2026

What is CVE-2026-33534?

EspoCRM versions 9.3.3 and earlier exhibit a vulnerability that enables Server-Side Request Forgery (SSRF). This flaw arises from the HostCheck::isNotInternalHost() function, which inadequately verifies host addresses, particularly when alternative IPv4 representations are used. Attackers can exploit this weakness through the /api/v1/Attachment/fromImageUrl endpoint, allowing authenticated users to compel the server to access loopback services. Although the validation mechanism employs PHP's filter_var, it fails to recognize certain IP formats, which can lead to unauthorized disclosure of internal resources. This issue has been rectified in version 9.3.4.

Affected Version(s)

espocrm < 9.3.4

References

https://github.com/espocrm/espocrm/security/advisories/GH...
x_refsource_CONFIRM
https://github.com/espocrm/espocrm/releases/tag/9.3.4
x_refsource_MISC

CVSS V3.1

Score:
4.3
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
None
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.