What’s Vulnerable › Vulnerabilities

CVE-2020-26238: Critical vulnerability found in cron-utils

• Severity: high (CVSS 8.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 4.2% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2020-11-25 · updated 2026-06-17
• Weakness: CWE-74

Description

Cron-utils is a Java library to parse, validate, migrate crons as well as get human readable descriptions for them. In cron-utils before version 9.1.3, a template Injection vulnerability is present. This enables attackers to inject arbitrary Java EL expressions, leading to unauthenticated Remote Code Execution (RCE) vulnerability. Only projects using the @Cron annotation to validate untrusted Cron expressions are affected. This issue was patched in version 9.1.3.

Affected products

• jmrozanec cron-utils: before 9.1.3 — fixed in 9.1.3

How to fix

Upgrade to a fixed version: jmrozanec cron-utils 9.1.3. Check the vendor advisory for mitigations.

References

• https://github.com/jmrozanec/cron-utils/commit/4cf373f7352f5d95f0bf6512af8af326b31c835e
• https://github.com/jmrozanec/cron-utils/issues/461
• https://github.com/jmrozanec/cron-utils/security/advisories/GHSA-pfj3-56hm-jwq5
• https://lists.apache.org/thread.html/r390bb7630b7ea8f02bf7adbbe69c0ae8b562c527d663c543d965f959%40%3Cgitbox.hive.apache.org%3E
• https://lists.apache.org/thread.html/r432a69a1a85cbcb1f1bad2aa0fbfce0367bf894bf917f6ed7118e7f0%40%3Cissues.hive.apache.org%3E
• https://lists.apache.org/thread.html/r50e1b5544c37e408ed7e9a958b28237b1cb9660ba2b3dba46f343e23%40%3Cissues.hive.apache.org%3E
• https://lists.apache.org/thread.html/r5f601d15292e3302ad0ae0e89527029546945b1cd5837af7e838d354%40%3Cdev.hive.apache.org%3E
• https://lists.apache.org/thread.html/r71083c759dc627f198571b3d48b6745fe798b1d53c34f7ef8de9e7dd%40%3Cissues.hive.apache.org%3E
• https://lists.apache.org/thread.html/r737406bc17d49ffe8fe6a8828d390ee0a02e45e5a5b4f931180b9a93%40%3Cissues.hive.apache.org%3E
• https://lists.apache.org/thread.html/r855aead591697dc2e85faf66c99036e49f492431940b78d4e6d895b5%40%3Cgitbox.hive.apache.org%3E
• https://lists.apache.org/thread.html/r96937fc9c82f3201b59311c067e97bce71123944f93102169a95bf5c%40%3Cissues.hive.apache.org%3E
• https://lists.apache.org/thread.html/r9ae9a9fb1c8e2bf95c676e7e4cd06aa04f0a3a8a9ec1a6b787afb00f%40%3Cissues.hive.apache.org%3E

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