[tor-bugs] #8037 [- Select a component]: Specialy crafter microdesc could trigger to flush up to 16MB uninited heap allocated memory to media

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#8037: Specialy crafter microdesc could trigger to flush up to 16MB uninited heap
allocated memory to media
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 Reporter:  cypherpunks           |          Owner:     
     Type:  defect                |         Status:  new
 Priority:  normal                |      Milestone:     
Component:  - Select a component  |        Version:     
 Keywords:                        |         Parent:     
   Points:                        |   Actualpoints:     
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 microdescs_parse_from_string() and so on func do not count string as null
 terminated and allows to process "string" with zero byte in middle.
 md->body = tor_strndup(cp, md->bodylen) duplicate only partial of such
 string. dump_microdescriptor() flushes all bodylen of md's body to disk.
 Specially crafted bytes append to valid md sent by directory cache could
 lead to flush up to 16MB of memory data to media. Tor tries to clear
 sensitive data on free(), but some non cleared memory still no need to
 write in plain text to media.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/8037>
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