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zipimport.zipimporter raises UnicodeDecodeError instead of ZipImportError for an invalid UTF-8 file name #153679
Description
Bug description
zipimport.zipimporter() is documented to raise zipimport.ZipImportError
for an invalid archive, but it leaks a raw UnicodeDecodeError when a central
directory entry sets the UTF-8 file name flag (0x800) yet stores bytes that
are not valid UTF-8.
In _read_directory() (Lib/zipimport.py) the UTF-8 branch does
name = name.decode() with no error handling, whereas the sibling non-UTF-8
branch already guards UnicodeDecodeError and falls back to latin-1/cp437.
Every other corruption path in the function raises ZipImportError.
>>> import struct, zipimport
>>> name = b'\xff\xfe\xff'
>>> cdh = b'PK\x01\x02' + struct.pack('<HHHHHHIIIHHHHHII', 20,20,0x800,0,0,0,0,50,100,len(name),0,0,0,0,0,0) + name
>>> eocd = b'PK\x05\x06' + struct.pack('<HHHHIIH', 0,0,1,1,len(cdh),0,0)
>>> _ = open('bad.zip','wb').write(cdh + eocd)
>>> zipimport.zipimporter('bad.zip')
Traceback (most recent call last):
...
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xff in position 0: invalid start byteExpected: zipimport.ZipImportError.
CPython versions tested on
3.13, 3.14, 3.15
Operating systems tested on
Linux, macOS
Activity
pythongh-153679: Trim the test comment and NEWS wording
gh-153679: Raise `ZipImportError` for an invalid UTF-8 file name in `…
StanFromIreland commentedon Oct 24, 2026
Thanks for the repirt and fix!
[3.14] gh-153679: Raise `ZipImportError` for an invalid UTF-8 file na…
[3.15] gh-153679: Raise `ZipImportError` for an invalid UTF-8 file na…