diff -Nru apt-cacher-1.7.29/apt-cacher-cleanup.pl apt-cacher-1.7.30/apt-cacher-cleanup.pl
--- apt-cacher-1.7.29/apt-cacher-cleanup.pl	2023-01-16 19:52:02.000000000 +0000
+++ apt-cacher-1.7.30/apt-cacher-cleanup.pl	2023-07-02 16:44:20.000000000 +0000
@@ -819,6 +819,7 @@
 
     foreach (glob('*{,/*}')) {
 	next if -d; # Skip directories
+	(my $vkey = $_) =~ s/%5f/_/g; # Decode embedded underscores
 	if (/([-+.a-z0-9]+_(?:\d:)?[-+.~a-zA-Z0-9]+)_changelog$/ && !$svrhash{$1}) { # Changelogs
 	    unlink $_, "../headers/$_" unless $sim_mode;
 	    printmsg "Removing expired changelog: $_ and company...\n";
@@ -830,23 +831,23 @@
 	}
 	elsif (is_file_type('package', $_) or is_file_type('pdiff', get_original_url($_))) { # Package and pdiff files
 
-	    if (! defined($valid{$_})) {
+	    if (! defined($valid{$vkey})) {
 		unlink $_, "../headers/$_", "../private/$_.complete" unless $sim_mode;
 		printmsg "Removing file: $_ and company...\n";
 	    } else {
-		# Verify SHA1 checksum
-		my $target_sum = hashify(\$valid{$_})->{sha1};
+		# Verify SHA256 checksum
+		my $target_sum = hashify(\$valid{$vkey})->{sha256};
 		next unless $target_sum;
-		# print "Validating SHA1 $target_sum for $_\n";
+		# print "Validating SHA256 $target_sum for $_\n";
 		open(my $fh, '<', $_) || die "Unable to open file $_ to verify checksum: $!";
 		flock($fh, LOCK_EX);
 		if (is_file_type('pdiff', get_original_url($_))) { # pdiffs need decompressing
 		    $fh = IO::Uncompress::AnyUncompress->new($fh)
 		      or die "Decompression failed: $AnyUncompressError\n";
 		}
-		if ((my $sha1 = Digest::SHA->new(1)->addfile($fh)->hexdigest) ne $target_sum) {
+		if ((my $sha256 = Digest::SHA->new(256)->addfile($fh)->hexdigest) ne $target_sum) {
 		    unlink $_, "../headers/$_", "../private/$_.complete" unless $sim_mode;
-		    printmsg "Checksum mismatch ($target_sum <=> $sha1): $_, removing\n";
+		    printmsg "Checksum mismatch ($target_sum <=> $sha256): $_, removing\n";
 		}
 		# No explicit LOCK_UN: it fails with IO::Uncompress::AnyUncompress, just rely on close
 		close $fh;
@@ -861,7 +862,8 @@
 
 foreach (glob('*{,/*}')) {
     next if -d; # Skip directories
-    if((is_file_type('package', $_) && !defined($valid{$_})) # Not indexed
+    (my $vkey = $_) =~ s/%5f/_/g; # Decode embedded underscores
+    if((is_file_type('package', $_) && !defined($valid{$vkey})) # Not indexed
        || !-e "../packages/$_") { # No corresponding package
 	unlink $_, "../private/$_.complete" unless $sim_mode;
 	printmsg "Removing expired headers: $_ and company...\n";
@@ -870,7 +872,7 @@
     my $resp = read_header($_);
     next if $resp && $resp->is_success; # Don't cache errors any more
     printmsg "Removing cached error/invalid response: $_\n";
-    delete $valid{$_};
+    delete $valid{$vkey};
     unlink $_ unless $sim_mode;
 }
 
diff -Nru apt-cacher-1.7.29/debian/changelog apt-cacher-1.7.30/debian/changelog
--- apt-cacher-1.7.29/debian/changelog	2023-01-16 19:52:02.000000000 +0000
+++ apt-cacher-1.7.30/debian/changelog	2023-07-02 16:44:20.000000000 +0000
@@ -1,3 +1,13 @@
+apt-cacher (1.7.30) unstable; urgency=medium
+
+  * d/control:
+    - remove obsolete lsb-base Depends.
+    - promote libio-compress-lzma-perl to Depends (Closes: #1039907).
+  * Decode embedded underscores in filenames when cleaning and validating cache.
+  * When cleaning and validating cached files, use SHA256.
+
+ -- Mark Hindley <mark@hindley.org.uk>  Sun, 02 Jul 2023 17:44:20 +0100
+
 apt-cacher (1.7.29) unstable; urgency=medium
 
   * Derive supported_archs default from Dpkg::Arch, based
diff -Nru apt-cacher-1.7.29/debian/control apt-cacher-1.7.30/debian/control
--- apt-cacher-1.7.29/debian/control	2023-01-16 19:52:02.000000000 +0000
+++ apt-cacher-1.7.30/debian/control	2023-07-02 16:44:20.000000000 +0000
@@ -16,6 +16,7 @@
          ed,
          libdpkg-perl,
          libfilesys-df-perl,
+	 libio-compress-lzma-perl,
          libio-interactive-perl,
          libio-interface-perl,
          libipc-sharelite-perl,
@@ -23,11 +24,10 @@
          libsys-syscall-perl,
          libwww-curl-perl,
          libwww-perl,
-         lsb-base (>= 3.2-14),
          update-inetd,
          ${misc:Depends},
          ${perl:Depends},
-Recommends: libberkeleydb-perl, libio-compress-lzma-perl
+Recommends: libberkeleydb-perl
 Suggests: libfreezethaw-perl, libio-socket-inet6-perl
 Description: Caching proxy server for Debian/Ubuntu/Devuan software repositories
  Apt-cacher performs caching of files requested by apt-get (or other APT clients