CVE-2022-36007 (published 2022-08-15T11:21Z)

Venice is a Clojure inspired sandboxed Lisp dialect with excellent Java interoperability. A partial path traversal issue exists within the functions `load-file` and `load-resource`. These functions can be limited to load files from a list of load paths. Assuming Venice has been configured with the load paths: `[ "/Users/foo/resources" ]` When passing **relative** paths to these two vulnerable functions everything is fine: `(load-resource "test.png")` => loads the file "/Users/foo/resources/test.png" `(load-resource "../resources-alt/test.png")` => rejected, outside the load path When passing **absolute** paths to these two vulnerable functions Venice may return files outside the configured load paths: `(load-resource "/Users/foo/resources/test.png")` => loads the file "/Users/foo/resources/test.png" `(load-resource "/Users/foo/resources-alt/test.png")` => loads the file "/Users/foo/resources-alt/test.png" !!! The latter call suffers from the _Partial Path Traversal_ vulnerability. This issue’s scope is limited to absolute paths whose name prefix matches a load path. E.g. for a load-path `"/Users/foo/resources"`, the actor can cause loading a resource also from `"/Users/foo/resources-alt"`, but not from `"/Users/foo/images"`. Versions of Venice before and including v1.10.17 are affected by this issue. Upgrade to Venice >= 1.10.18, if you are on a version < 1.10.18. There are currently no known workarounds.

CVSS v3 base score: 3.3, LOW (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N)

Weakness information:
cwe_id: CWE-22
cwe_name: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
description: The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.
extended_description: 
            Many file operations are intended to take place within a restricted directory. By using special elements such as ".." and "/" separators, attackers can escape outside of the restricted location to access files or directories that are elsewhere on the system. One of the most common special elements is the "../" sequence, which in most modern operating systems is interpreted as the parent directory of the current location. This is referred to as relative path traversal. Path traversal also covers the use of absolute pathnames such as "/usr/local/bin" to access unexpected files. This is referred to as absolute path traversal.
         
         

Fix information:
repo_url: https://github.com/jlangch/venice
commit_details: repo_url: https://github.com/jlangch/venice
author: jlangch
author_date: 2022-07-29 21:14:00+02:00
msg: Merge pull request #4 from BulkSecurityGeneratorProjectV2/fix/JLL/partial-path-traversal-vulnerability

[SECURITY] Fix Partial Path Traversal Vulnerability
repository: repo_url: https://github.com/jlangch/venice
repo_name: jlangch/venice
description:  Venice, a Clojure inspired sandboxed Lisp dialect with Java interoperability serving as a safe scripting language.
repo_language: Java
owner: jlangch
repo_url: https://github.com/jlangch/venice
commit_details: repo_url: https://github.com/jlangch/venice
author: Jonathan Leitschuh
author_date: 2022-07-29 13:38:50+00:00
msg: vuln-fix: Partial Path Traversal Vulnerability

This fixes a partial path traversal vulnerability.

Replaces `dir.getCanonicalPath().startsWith(parent.getCanonicalPath())`, which is vulnerable to partial path traversal attacks, with the more secure `dir.getCanonicalFile().toPath().startsWith(parent.getCanonicalFile().toPath())`.

To demonstrate this vulnerability, consider `"/usr/outnot".startsWith("/usr/out")`.
The check is bypassed although `/outnot` is not under the `/out` directory.
It's important to understand that the terminating slash may be removed when using various `String` representations of the `File` object.
For example, on Linux, `println(new File("/var"))` will print `/var`, but `println(new File("/var", "/")` will print `/var/`;
however, `println(new File("/var", "/").getCanonicalPath())` will print `/var`.

Weakness: CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Severity: Medium
CVSSS: 6.1
Detection: CodeQL & OpenRewrite (https://public.moderne.io/recipes/org.openrewrite.java.security.PartialPathTraversalVulnerability)

Reported-by: Jonathan Leitschuh <Jonathan.Leitschuh@gmail.com>
Signed-off-by: Jonathan Leitschuh <Jonathan.Leitschuh@gmail.com>

Bug-tracker: https://github.com/JLLeitschuh/security-research/issues/13

Co-authored-by: Moderne <team@moderne.io>
repository: repo_url: https://github.com/jlangch/venice
repo_name: jlangch/venice
description:  Venice, a Clojure inspired sandboxed Lisp dialect with Java interoperability serving as a safe scripting language.
repo_language: Java
owner: jlangch
file_changes: filename: LoadPaths.java
change_type: ModificationType.MODIFY
diff: @@ -258,7 +258,7 @@ public class LoadPaths implements ILoadPaths {
         if (dir_.isDirectory()) {
             final File fl = new File(dir_, file.getPath());
             if (fl.isFile()) {
-                if (fl.getCanonicalPath().startsWith(dir_.getCanonicalPath())) {
+                if (fl.getCanonicalFile().toPath().startsWith(dir_.getCanonicalFile().toPath())) {
                     // Prevent accessing files outside the load-path.
                     // E.g.: ../../coffee
                     return true;

programming_language: Java