What’s Vulnerable › Vulnerabilities

CVE-2021-23521: Link Following

• Severity: high (CVSS 7.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2022-01-31 · updated 2026-06-17
• Weakness: CWE-59

Description

This affects the package juce-framework/JUCE before 6.1.5. This vulnerability is triggered when a malicious archive is crafted with an entry containing a symbolic link. When extracted, the symbolic link is followed outside of the target dir allowing writing arbitrary files on the target host. In some cases, this can allow an attacker to execute arbitrary code. The vulnerable code is in the ZipFile::uncompressEntry function in juce_ZipFile.cpp and is executed when the archive is extracted upon calling uncompressTo() on a ZipFile object.

Affected products

• Juce: before 6.1.5 — fixed in 6.1.5

How to fix

Upgrade to a fixed version: Juce 6.1.5. Check the vendor advisory for mitigations.

References

• https://github.com/juce-framework/JUCE/commit/2e874e80cba0152201aff6a4d0dc407997d10a7f
• https://snyk.io/vuln/SNYK-UNMANAGED-JUCEFRAMEWORKJUCE-2388608
• https://github.com/juce-framework/JUCE/commit/2e874e80cba0152201aff6a4d0dc407997d10a7f
• https://snyk.io/vuln/SNYK-UNMANAGED-JUCEFRAMEWORKJUCE-2388608

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