View at Official ubuntu advisory, NVD, CVE.org · CVE detail
Freshness: upstream tracker timestamp is available; use API updated time as primary recency signal.
CVE-2004-2771 medium priority: Ubuntu including 2 source packages (bsd-mailx, heirloom-mailx), 20 status rows across 10 suites (lucid, precise, trusty, upstream, utopic, vivid, wily, xenial, yakkety, zesty): not-affected 11, DNE 3, ignored 2, needs-triage 2, released 2.
The expand function in fio.c in Heirloom mailx 12.5 and earlier and BSD mailx 8.1.2 and earlier allows remote attackers to execute arbitrary commands via shell metacharacters in an email address.