CVE-2026-53421Network attack vector

Administrator RCE via scripted connector Groovy

Published Jul 20, 2026 · Updated Jul 20, 2026

Improper isolation in Apache Syncope allows remote authenticated users to execute code on the server through REST or SQL scripted connectors. The connector subsystem runs administrator-supplied Groovy in scripted connectors without a sufficiently hardened security sandbox. Administrative connector entitlements are required, and successful exploitation runs Groovy code with the Syncope server's privileges.

CVSS severity9.8
Critical
EPSS probability0.68%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper isolation in Apache Syncope allows remote authenticated users to execute code on the server through REST or SQL scripted connectors. The connector subsystem runs administrator-supplied Groovy in scripted connectors without a sufficiently hardened security sandbox. Administrative connector entitlements are required, and successful exploitation runs Groovy code with the Syncope server's privileges.

The record

CVE
CVE-2026-53421
Published
Jul 20, 2026
Updated
Jul 20, 2026
Vendor
The Apache Software Foundation
Product
Apache Syncope
Classifications
CWE-653, T1059
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Jul 20, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 20, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=3.0.0-M0 <=3.0.16
  2. Affected versionversion=4.0.0-M0 <=4.0.6
  3. Affected versionversion=4.1.0-M0 <=4.1.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

The Apache Software Foundation · Apache Syncopeversion=3.0.0-M0 <=3.0.16; version=4.0.0-M0 <=4.0.6; version=4.1.0-M0 <=4.1.1

Published CVSS scores

9.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-653Improper Isolation or Compartmentalization
T1059Command and Scripting Interpreter

Public exploit references

No public exploit references are available in this record.

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

Technologies

Your stack

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Your stack

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