contain assay file reads within the isa-tab directory

tika-parsers/tika-parsers-extended/tika-parser-scientific-module/src/main/java/org/apache/tika/parser/isatab/ISArchiveParser.java

@@ -138,11 +138,26 @@ private void parseAssay(XHTMLContentHandler xhtml, Metadata metadata, ParseConte
             xhtml.startElement("div");
             xhtml.element("h3", "ASSAY " + assayFileName);
             // location starts with "/C:" on windows, can't use Paths.get()
-            try (InputStream stream = TikaInputStream.get(new File(this.location + assayFileName).toPath()))
-            {
+            File assayFile = resolveWithinLocation(assayFileName);
+            try (InputStream stream = TikaInputStream.get(assayFile.toPath())) {
                 ISATabUtils.parseAssay(stream, xhtml, metadata, context);
             }
             xhtml.endElement("div");
         }
     }
+
+    /**
+     * Resolves an assay file name taken from the (untrusted) investigation file against
+     * the ISA-Tab location, rejecting names that escape that directory via "../" or a
+     * symlink.
+     */
+    private File resolveWithinLocation(String fileName) throws IOException, TikaException {
+        File candidate = new File(this.location + fileName);
+        String locationCanonical = new File(this.location).getCanonicalPath();
+        if (!candidate.getCanonicalPath().startsWith(locationCanonical + File.separator)) {
+            throw new TikaException(
+                    "assay file name '" + fileName + "' resolves outside the ISA-Tab directory");
+        }
+        return candidate;
+    }
 }

tika-parsers/tika-parsers-extended/tika-parser-scientific-module/src/test/java/org/apache/tika/parser/isatab/ISArchiveParserTest.java

@@ -17,11 +17,19 @@
 package org.apache.tika.parser.isatab;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
 
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
 import org.xml.sax.ContentHandler;
 
 import org.apache.tika.TikaTest;
+import org.apache.tika.exception.TikaException;
 import org.apache.tika.io.TikaInputStream;
 import org.apache.tika.metadata.Metadata;
 import org.apache.tika.metadata.TikaCoreProperties;
@@ -68,4 +76,32 @@ public void testParseArchive() throws Exception {
         assertEquals("Stephen", metadata.get("Investigation Person First Name"),
                 "Invalid Investigation Person First Name");
     }
+
+    @Test
+    public void testAssayPathTraversal(@TempDir Path root) throws Exception {
+        Path secret = root.resolve("secret.txt");
+        Files.write(secret, "SUPERSECRETTOKEN12345".getBytes(StandardCharsets.UTF_8));
+
+        Path isaDir = Files.createDirectory(root.resolve("isa"));
+        Files.write(isaDir.resolve("i_test.txt"),
+                ("STUDY\n"
+                        + "Study File Name\t\"s_test.txt\"\n"
+                        + "Study Assay File Name\t\"../secret.txt\"\n")
+                        .getBytes(StandardCharsets.UTF_8));
+        Path study = isaDir.resolve("s_test.txt");
+        Files.write(study, "\"Source Name\"\n\"culture1\"\n".getBytes(StandardCharsets.UTF_8));
+
+        Parser parser = new ISArchiveParser(isaDir.toString());
+        ContentHandler handler = new BodyContentHandler();
+        Metadata metadata = new Metadata();
+        metadata.set(TikaCoreProperties.RESOURCE_NAME_KEY, "s_test.txt");
+        ParseContext context = new ParseContext();
+
+        try (TikaInputStream tis = TikaInputStream.get(study)) {
+            assertThrows(TikaException.class,
+                    () -> parser.parse(tis, handler, metadata, context));
+        }
+        assertFalse(handler.toString().contains("SUPERSECRETTOKEN12345"),
+                "assay reader escaped the ISA-Tab directory");
+    }
 }