<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>On Nov 4, 2010, at 12:49 PM, Guido van Rossum wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; font-family: Menlo; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><span class="Apple-style-span" style="font-family: monospace; ">What's the attack you're thinking of on marshal? It never executes any<br>code while unmarshalling (although it can unmarshal code objects --<br>but the receiving program has to do something additionally to execute<br>those).<br></span></span></blockquote></div><br><div>These issues may have been fixed now, but a long time ago I recall seeing some nasty segfaults which looked exploitable when feeding marshal malformed data. If they still exist, running a fuzzer on some pyc files should reveal them pretty quickly.</div><div><br></div><div>When I ran across them I didn't think much of them, and probably did not even report the bug, since marshal is mostly used to load code anyway, which is implicitly trusted.</div><div><br></div></body></html>