Gwenhywfar 5.14.2 contains a heap use-after-free vulnerability in GWEN_TLV_Buffer_To_DB() in src/parser/tlv.c, which frees a nested record's GWEN_DB node when parsing of its contents fails but continues processing and adds the freed node to the parent instead of returning. Attackers can supply a constructed BER-TLV record with unparseable contents, such as via a malicious chip card read by libchipcard, to corrupt heap memory.