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Integer overflow in nginx

securityfocus.com
12 pointsqzio3 comments
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Looking for details..

haven't contacted the author but he describes his supposed route. I'm trying to replicate his results and there is indeed a possible integer overflow condition but I'd be doubtful of reports of successful exploitation with systems linked with a newer version of glibc w/ heap consistency checking, stackguard &/| aslr.

http://lxr.evanmiller.org/http/source/core/ngx_log.h#L120 contains a few functions (2, 5 I've found so far) that write data in a (at a quick glance) safe fashion, I guess you might be able to give someone wierd logfiles.

I've been over every file that referenced by ngx_http_request_t http://lxr.evanmiller.org/http/ident?i=ngx_http_request_t looking for buffers, directly or indirectly using a value derived from a ngx_http_request->count (not -> main -> count), and although the bug condition he describes is possibly real, I'd love to see an RCE proof of concept from the author.

qzioOP

MM, I'm not sure if this is real or not... Need more info

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