/usr/share/lintian/overrides/liburi-escape-xs-perl is in liburi-escape-xs-perl 0.14-1+b1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | # false positive, according to blhc and manual inspection
liburi-escape-xs-perl: hardening-no-fortify-functions usr/lib/*/auto/URI/Escape/XS/XS.so
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