An issue was discovered in the Tatsuya Kinoshita w3m fork before 0.5.3-31. Integer overflow vulnerability in the renderTable function in w3m allows remote attackers to cause a denial of service (OOM) and possibly execute arbitrary code due to bdwgc's bug (CVE-2016-9427) via a crafted HTML page.
https://security.gentoo.org/glsa/201701-08
https://github.com/tats/w3m/issues/25
https://github.com/tats/w3m/blob/master/ChangeLog