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Mallory
Medium

XXE in Apache Syncope Console Keymaster parameters handling

IdentifiersCVE-2026-23795CWE-611· Improper Restriction of XML…

Apache Syncope Console contains an Improper Restriction of XML External Entity Reference (XXE) flaw in the functionality used to create or edit Keymaster parameters via the Console. An administrator with sufficient entitlements can supply crafted malicious XML that triggers external entity resolution during XML parsing, enabling unintended retrieval of sensitive data (e.g., local file disclosure and/or access to internal network resources) through XXE behavior. Affected versions are Apache Syncope Console 3.0 through 3.0.15 and 4.0 through 4.0.3.

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ANALYST BRIEF

Impact, mitigation & remediation

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Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation can result in sensitive data leakage from the Syncope server environment via XXE, including disclosure of arbitrary local files and potential access to internal network resources reachable by the server (SSRF-like effects via entity resolution). The provided content also notes potential exposure of session tokens/authentication credentials and possible session hijacking implications in some scenarios.

Mitigation

If you can’t patch tonight, do this now.

If immediate upgrade is not possible, restrict and tightly control which administrators have entitlements to create or edit Keymaster parameters in the Syncope Console; audit/monitor Keymaster parameter changes for suspicious XML content and monitor for anomalous XML parsing/entity-resolution activity.

Remediation

Patch, then assume compromise.

Upgrade to Apache Syncope Console 3.0.16 (3.0.x line) or 4.0.4 (4.0.x line), which address the XXE condition in Keymaster parameters handling.
PUBLIC EXPLOITS

Exploits

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VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

EXPOSURE SURFACE

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VendorProductType
Apache Software FoundationSyncopeapplication

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Threat actor evidence

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Associated malware

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Detection signatures

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Social activity3

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