BIT-PYTHON-MIN-2026-6100 Use-after-free in lzma.LZMADecompressor, bz2.BZ2Decompressor, and gzip.GzipFile after re-use under memory pressure

Use-after-free UAF was possible in the lzma.LZMADecompressor, bz2.BZ2Decompressor, and gzip.GzipFile when a memory allocation fails with a MemoryError and the decompression instance is re-used. This scenario can be triggered if the process is under memory pressure. The fix cleans up the dangling...

BIT-PYTHON-2026-9669 bz2.BZ2Decompressor reuse after error can cause a stack buffer overflow

bz2.BZ2Decompressor objects could be reused after a decompression error. If an application caught the resulting OSError and retried with the same decompressor, crafted input could cause the decompressor to resume from an invalid internal state and perform out-of-bounds writes to a stack buffer...

bz2.BZ2Decompressor reuse after error can cause a stack buffer overflow

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CVE-2026-9669

A flaw was found in Python's bz2.BZ2Decompressor component. An attacker could provide specially crafted input that, when processed by an application reusing a decompressor object after an error, could lead to out-of-bounds writes in memory. This memory corruption could cause the application to...

DEBIAN-CVE-2026-9669

bz2.BZ2Decompressor objects could be reused after a decompression error. If an application caught the resulting OSError and retried with the same decompressor, crafted input could cause the decompressor to resume from an invalid internal state and perform out-of-bounds writes to a stack buffer...

CVE-2026-9669

bz2.BZ2Decompressor objects could be reused after a decompression error. If an application caught the resulting OSError and retried with the same decompressor, crafted input could cause the decompressor to resume from an invalid internal state and perform out-of-bounds writes to a stack buffer...

CVE-2026-9669 bz2.BZ2Decompressor reuse after error can cause a stack buffer overflow

bz2.BZ2Decompressor objects could be reused after a decompression error. If an application caught the resulting OSError and retried with the same decompressor, crafted input could cause the decompressor to resume from an invalid internal state and perform out-of-bounds writes to a stack buffer...

CVE-2026-9669 bz2.BZ2Decompressor reuse after error can cause a stack buffer overflow

bz2.BZ2Decompressor objects could be reused after a decompression error. If an application caught the resulting OSError and retried with the same decompressor, crafted input could cause the decompressor to resume from an invalid internal state and perform out-of-bounds writes to a stack buffer...

CVE-2026-9669 bz2.BZ2Decompressor reuse after error can cause a stack buffer overflow

bz2.BZ2Decompressor objects could be reused after a decompression error. If an application caught the resulting OSError and retried with the same decompressor, crafted input could cause the decompressor to resume from an invalid internal state and perform out-of-bounds writes to a stack buffer...

CVE-2026-9669

The CVE affects Python’s bz2.BZ2Decompressor: objects could be reused after a decompression error, allowing an application that catches OSError and retries with the same decompressor to resume in an invalid internal state and perform out-of-bounds writes to a stack buffer, possibly crashing the p...