Use after free's / double free's can cause in memory corruption, that can cause a crash or other undefined (potentially exploitable) behaviour. Reproducible: Always CVE-2021-4173 vim is vulnerable to Use After Free URLs: https://nvd.nist.gov/vuln/detail/CVE-2021-4173 https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-4173 Fixed in patch 8.2.3902.
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