bug#60425: Maybe a security issue

[Fabio Luiz Barbosa]

Hi there,

so I was doing a test but am unsure if it is a bug from sed or a known
behavior from sed nor if it is considered a security issue.

On the test, I was able to "write" in a file that the permission is 400 the
only way to "avoid it" is to alter the permission to 000.

Using setfacl or other means to manipulate the permission level was not
effective.

If this is a known issue from sed, from internal sed "working way" or it
was already fixed in newer versions please do not consider this message.

====================================================================
sed --version
sed (GNU sed) 4.7
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