MSA-21-0024: Blind SSRF possible against cURL blocked hosts via redirect

by Michael Hawkins.  

Insufficient redirect handling made it possible to blindly bypass cURL blocked hosts/allowed ports restrictions, resulting in a blind SSRF risk. (Note: The request response was still blocked and not available to the user.)


Severity/Risk:Serious
Versions affected:3.11, 3.10 to 3.10.4, 3.9 to 3.9.7 and earlier unsupported versions
Versions fixed:3.11.1, 3.10.5 and 3.9.8
Reported by:Rekter0 and Holme
CVE identifier:CVE-2021-36396
Changes (master):http://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-71916
Tracker issue:MDL-71916 Blind SSRF possible against cURL blocked hosts via redirect

Read more https://moodle.org/mod/forum/discuss.php?d=424802&parent=1710821