THREATPORT/VULNERABILITY/CVE-2020-1959
CRITICAL SEVERITY

CVE-2020-1959

Syncope vulnerability

CVSS
9.8
EPSS
4.8%
EPSS pct
91th
Exploited
No known
A Server-Side Template Injection was identified in Apache Syncope prior to 2.1.6 enabling attackers to inject arbitrary Java EL expressions, leading to an unauthenticated Remote Code Execution (RCE) vulnerability. Apache Syncope uses Java Bean Validation (JSR 380) custom constraint validators. When building custom constraint violation error messages, they support different types of interpolation, including Java EL expressions. Therefore, if an attacker can inject arbitrary data in the error message template being passed, they will be able to run arbitrary Java code.
Affected vendor
Apache
Affected product
Syncope
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness type (CWE)
  • CWE-917 — Expression Language Injection
Published
2020-05-04

Risk analysis

Based on its CVSS vector, this vulnerability is exploitable over the network, low attack complexity, requiring no privileges, no user interaction. Successful exploitation leads to high impact to confidentiality, high impact to integrity, high impact to availability.

Its EPSS score of 4.8% reflects a lower probability of exploitation activity in the wild over the next 30 days, placing it above 91% of all scored CVEs.

Check your external exposure to CVE-2020-1959

  • Confirm whether Apache Syncope is running on any internet-facing host or subdomain.
  • Match discovered service fingerprints against the version affected by CVE-2020-1959.
  • Prioritise remediation if the asset is public, business-critical, or near authentication/payment flows.

How ThreatPort helps with CVE-2020-1959

ThreatPort's external attack surface scanner checks your internet-facing assets — agentlessly, from the outside in — for the exposed services and versions that CVE-2020-1959 affects, then prioritises the finding by real risk using CISA KEV and FIRST.org EPSS.

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