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