Impact
In express <4.20.0, passing untrusted user input - even after sanitizing it - to response.redirect()
may execute untrusted code
Patches
this issue is patched in express 4.20.0
Workarounds
users are encouraged to upgrade to the patched version of express, but otherwise can workaround this issue by making sure any untrusted inputs are safe, ideally by validating them against an explicit allowlist
Details
successful exploitation of this vector requires the following:
- The attacker MUST control the input to response.redirect()
- express MUST NOT redirect before the template appears
- the browser MUST NOT complete redirection before:
- the user MUST click on the link in the template
Impact
In express <4.20.0, passing untrusted user input - even after sanitizing it - to
response.redirect()
may execute untrusted codePatches
this issue is patched in express 4.20.0
Workarounds
users are encouraged to upgrade to the patched version of express, but otherwise can workaround this issue by making sure any untrusted inputs are safe, ideally by validating them against an explicit allowlist
Details
successful exploitation of this vector requires the following: