Vulnerability record · CVE-2020-17521 · published 7 December 2020
CVE-2020-17521: Apache groovy vulnerability
Apache · Groovy
Apache Groovy provides extension methods to aid with creating temporary directories. Prior to this fix, Groovy's implementation of those extension methods was using a now superseded Java JDK method call that is potentially not secure on some operating systems in some contexts. Users not using the extension methods mentioned in the advisory are not affected, but may wish to read the advisory for further details. Versions Affected: 2.0 to 2.4.20, 2.5.0 to 2.5.13, 3.0.0 to 3.0.6, and 4.0.0-alpha-1. Fixed in versions 2.4.21, 2.5.14, 3.0.7, 4.0.0-alpha-2.
Description
Apache Groovy provides extension methods to aid with creating temporary directories. Prior to this fix, Groovy's implementation of those extension methods was using a now superseded Java JDK method call that is potentially not secure on some operating systems in some contexts. Users not using the extension methods mentioned in the advisory are not affected, but may wish to read the advisory for further details. Versions Affected: 2.0 to 2.4.20, 2.5.0 to 2.5.13, 3.0.0 to 3.0.6, and 4.0.0-alpha-1. Fixed in versions 2.4.21, 2.5.14, 3.0.7, 4.0.0-alpha-2.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Affected products
21 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2020-17521), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.