feat: disallow file uploads for old Microsoft formats #1907
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Problem
We currently whitelist old Microsoft formats (
.doc,.ppt,.xls) for file uploads, but thefile-typelibrary that we use for detecting file types does not support them (documentation), and recognizes them as.cfbinstead. As Alexis notes, these old formats can also be weaponized and exploited for malicious uses, so we should disallow them anywaySolution
Remove
.doc,.ppt,.xlsfrom ourDEFAULT_ALLOWED_FILE_EXTENSIONSTests
.doc,.ppt,.xlsfiles are not allowed