GHSA-q9m2-fhv9-3jcf `potato-annotation` has a Project-Boundary Bypass

Not scored Published 8 May 2026

Attackers can bypass project boundary checks to access or modify files outside the intended directory due to flawed string-prefix validation.

Exploited in the wild: Not known
Login needed: Not stated
Attackable: Not stated
Victim action needed: Not needed
Fix: Available

What is GHSA-q9m2-fhv9-3jcf?

GHSA-q9m2-fhv9-3jcf is a path traversal vulnerability in potato-annotation, published on 8 May 2026.

Official description

Summary

validate_path_security uses string-prefix containment (startswith) for boundary checks. This allows paths that are outside the intended project directory but share its prefix string (e.g., /tmp/potato_proj_demo_evil/... vs /tmp/potato_proj_demo) to be accepted.

Details

Affected source location (root cause)

File: potato/server_utils/config_module.py

Snippet (lines 370–373):

real_path = os.path.realpath(normalized_path)
real_base = os.path.realpath(base_dir)
if not real_path.startswith(real_base):
    raise ConfigSecurityError(...)

Snippet (lines 384–389):

real_path = os.path.realpath(normalized_path)
check_dir = project_dir if project_dir else base_dir
real_check_dir = os.path.realpath(check_dir)
if not real_path.startswith(real_check_dir):
    raise ConfigSecurityError(...)

startswith() is string-based, so /tmp/potato_proj_demo_evil/... passes when checked against /tmp/potato_proj_demo.

Confirmed affected call sites

File: potato/server_utils/config_module.py

validate_file_paths task_dir branch (line 2113)

validated_task_dir = validate_path_security(task_dir, project_dir)

validate_file_paths data_files branch (line 2151)

validated_path = validate_path_security(file_path, base_dir, project_dir)

validate_training_config training.data_file branch (line 2286)

validated_path = validate_path_security(data_file, base_dir, project_dir)

PoC

from potato.server_utils.config_module import validate_path_security

base = &#39;/tmp/potato_proj_demo&#39;
vuln = &#39;/tmp/potato_proj_demo_evil/file.txt&#39;

try:
    print(&#39;inside=&#39;, validate_path_security(&#39;/tmp/potato_proj_demo/file.txt&#39;, base, base))
except Exception as e:
    print(&#39;inside_error=&#39;, type(e).__name__, e)

try:
    validate_path_security(&#39;/tmp/other_demo/file.txt&#39;, base, base)
except Exception as e:
    print(&#39;baseline=&#39;, type(e).__name__, e)

print(&#39;trigger=&#39;, validate_path_security(vuln, base, base))

Impact

Can allow unauthorized sibling-prefix file access outside intended project boundary.
Can affect read paths (data_files, training.data_file, base_css, header_logo) and output/path placement depending on configuration.

Which versions are affected by GHSA-q9m2-fhv9-3jcf?

2 open source packages ship an affected version, including potato-annotation.

Package	Affected	Fixed in
`potato-annotation` PyPI	From `2.0.0`	`2.4.5`
`potato-annotation` PyPI	From `2.0.0`	`2.4.5`

How do I fix GHSA-q9m2-fhv9-3jcf?

Upgrade potato-annotation to 2.4.5 or later.

Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.

Is GHSA-q9m2-fhv9-3jcf being exploited?

There is no known exploitation of GHSA-q9m2-fhv9-3jcf in the wild and no public exploit code.