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Fix path traversal check in tar extraction to use path-aware comparison #42

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Merged
rilma merged 3 commits into from
Feb 21, 2026
Merged

Fix path traversal check in tar extraction to use path-aware comparison #42

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0669316
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Copilot Feb 21, 2026
1e6f71d
fix: use os.path.commonpath for path traversal check and raise ValueE…
Copilot Feb 21, 2026
00094e9
fix: handle ValueError from os.path.commonpath for cross-drive paths
Copilot Feb 21, 2026
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9 changes: 5 additions & 4 deletions pyiri2016/api/update.py
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Original file line number Diff line number Diff line change
Expand Up @@ -13,16 +13,17 @@ def is_within_directory(directory, target):
abs_directory = os.path.abspath(directory)
abs_target = os.path.abspath(target)

prefix = os.path.commonprefix([abs_directory, abs_target])

return prefix == abs_directory
try:
return os.path.commonpath([abs_directory, abs_target]) == abs_directory
except ValueError:
return False

def safe_extract(tar, path=".", members=None, *, numeric_owner=False):

for member in tar.getmembers():
member_path = os.path.join(path, member.name)
if not is_within_directory(path, member_path):
raise Exception("Attempted Path Traversal in Tar File")
raise ValueError("Attempted Path Traversal in Tar File")

tar.extractall(path, members, numeric_owner=numeric_owner)

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