archivereadformatrarreaddata in archivereadsupportformatrar.c in libarchive before 3.4.0 has a use-after-free in a certain ARCHIVEFAILED situation, related to Ppmd7_DecodeSymbol.
"https://storage.googleapis.com/osv-test-cve-osv-conversion/alpine/ALPINE-CVE-2019-18408.json"