News has emerged that Exim, the most popularly deployed piece of email transmission software, is confirmed to be remotely exploitable for version numbers between 4.87 and 4.91 (archived). There are claims that the exploitable portion of the software was accidentally fixed in version 4.92 released in February, though the historical trend for this sort of shennanigan suggests more plausibly that an intentional NOBUS backdoor was quietly tightented after the US set expanded.