CVE-2026-33659Public exploitNetwork attack vector

Authenticated SSRF via inconsistent DNS resolution

Published Apr 13, 2026 · Updated Apr 13, 2026

SSRF in EspoCRM 9.3.3 and earlier allows remote authenticated users to reach internal HTTP services through a crafted image URL. HostCheck::isNotInternalHost validates dns_get_record() results, but curl resolves the same hostname again and can receive a different, internal address; empty DNS results are also allowed. Default attachment-creation access is sufficient to scan internal ports, identify hosts, and interact with HTTP services, but the endpoint does not enable binary-service data extraction or code execution.

CVSS severity3.5
Low
EPSS probability0.33%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

SSRF in EspoCRM 9.3.3 and earlier allows remote authenticated users to reach internal HTTP services through a crafted image URL. HostCheck::isNotInternalHost validates dns_get_record() results, but curl resolves the same hostname again and can receive a different, internal address; empty DNS results are also allowed. Default attachment-creation access is sufficient to scan internal ports, identify hosts, and interact with HTTP services, but the endpoint does not enable binary-service data extraction or code execution.

The record

CVE
CVE-2026-33659
Published
Apr 13, 2026
Updated
Apr 13, 2026
Vendor
EspoCRM
Product
EspoCRM
Classifications
CWE-367, CWE-918, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 13, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 13, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 9.3.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

EspoCRM · EspoCRMversion=< 9.3.4

Published CVSS scores

3.1NIST NVDCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
3.5GitHub, Inc.CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-367Time-of-check Time-of-use (TOCTOU) Race Condition
CWE-918Server-Side Request Forgery (SSRF)
T1190Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo