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strtoul is too lax about characters which are used for numbers.
Manually check that masklength starts with digit.
PoC
Add following match block to your sshd_config
Match address "127.0.0.1/ +0032"
ForceCommand ls
If you access your server with `ssh 127.0.0.1` then ls is executed.
This behaviour is unexpected as masklength should not be valid.
Contributor
|
committed upstream and synced back as fda1eaaec - thanks! |
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strtoul is too lax about characters which are used for numbers.
Manually check that masklength starts with digit.
PoC
Add following match block to your sshd_config
Match address "127.0.0.1/ +0032"
ForceCommand ls
If you access your server with
ssh 127.0.0.1then ls is executed.This behaviour is unexpected as masklength should not be valid.
Shoutout to @c3h2_ctf