HT is a hex editor, designed to help analyse and modify executable files.
Tavis Ormandy of the Gentoo Linux Security Team discovered an integer overflow in the ELF parser, leading to a heap-based buffer overflow. The vendor has reported that an unrelated buffer overflow has been discovered in the PE parser.
Successful exploitation would require the victim to open a specially crafted file using HT, potentially permitting an attacker to execute arbitrary code.
There is no known workaround at this time.
All hteditor users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=app-editors/hteditor-0.8.0-r2"