CVE-2020-1961 Injection in Apache Syncope

What is CVE-2020-1961?

CVE-2020-1961 is a critical code injection vulnerability in Apache Syncope, published on 4 May 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Vulnerability to Server-Side Template Injection on Mail templates for Apache Syncope 2.0.X releases prior to 2.0.15, 2.1.X releases prior to 2.1.6, enabling attackers to inject arbitrary JEXL expressions, leading to Remote Code Execution (RCE) was discovered.

Weakness: CWE-74

Which versions are affected by CVE-2020-1961?

4 open source packages ship an affected version, including org.apache.syncope:syncope-core. It affects 1 product.

Products include Apache Syncope.

How do I fix CVE-2020-1961?

Upgrade org.apache.syncope:syncope-core to a fixed version for your release line: 2.0.15 or 2.1.6.

Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.

Is CVE-2020-1961 being exploited?

There is no known exploitation of CVE-2020-1961 in the wild and no public exploit code.

Other vulnerabilities in Apache Syncope

• CVE-2026-53405 Apache Syncope: Remote Code Execution via Flowable BPMN Groovy ScriptTask Critical 9.8
• CVE-2026-53421 Apache Syncope: Remote Code Execution via Scripted Connector Critical 9.8
• CVE-2026-57308 Apache Syncope: SQL injection vulnerability in Audit Events search Critical 9.8
• CVE-2026-62183 Apache Syncope: User self-service privilege escalation Critical 9.8
• CVE-2026-63071 Apache Syncope: RCE via Groovy Sandbox bypass Critical 9.8

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-4w4p-xwrr-9crh.