python: Python: Arbitrary code execution or information disclosure via use-after-free in decompression modules

A flaw was found in Python's decompression modules, including lzma.LZMADecompressor, bz2.BZ2Decompressor, and gzip.GzipFile. This vulnerability, a use-after-free, can occur if a program attempts to re-use a decompression object after a memory allocation error, especially when the system is...

FreeBSD : Python -- use-after-free vulnerability in decompressors under memory pressure (b8e9f33c-375d-11f1-a119-e36228bfe7d4)

The version of FreeBSD installed on the remote host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the b8e9f33c-375d-11f1-a119-e36228bfe7d4 advisory. Seth Larson reports: There is a CRITICAL severity vulnerability affecting CPython. Use-after-free UAF w...

Out-of-bounds Write

Overview Affected versions of this package are vulnerable to Out-of-bounds Write in the ReadCLen function of the Tiano decompressor. An attacker can cause a crash by supplying specially crafted compressed firmware data that triggers a heap out-of-bounds write during decompression. Remediation...

GHSA-HM2W-VR2P-HQ7W UEFI Firmware Parser has a heap out-of-bounds write in tiano decompressor ReadCLen

uefi-firmware contains a heap out-of-bounds write vulnerability in the native tiano/EFI decompressor. in uefifirmware/compression/Tiano/Decompress.c, ReadCLen reads Number = GetBitsSd, CBIT with CBIT = 9, so Number can be as large as 511, while the destination array Sd-mCLen has NC = 510 elements...

UEFI Firmware Parser has a heap out-of-bounds write in tiano decompressor ReadCLen

uefi-firmware contains a heap out-of-bounds write vulnerability in the native tiano/EFI decompressor. in uefifirmware/compression/Tiano/Decompress.c, ReadCLen reads Number = GetBitsSd, CBIT with CBIT = 9, so Number can be as large as 511, while the destination array Sd-mCLen has NC = 510 elements...

GHSA-2689-5P89-6J3J UEFI Firmware Parser has a stack out-of-bounds write in tiano decompressor MakeTable

uefi-firmware contains a stack out-of-bounds write vulnerability in the native tiano/EFI decompressor. in uefifirmware/compression/Tiano/Decompress.c, MakeTable does not validate that bit-length values read from the compressed bitstream are within the expected range 0..16. a crafted firmware blob...

UEFI Firmware Parser has a stack out-of-bounds write in tiano decompressor MakeTable

uefi-firmware contains a stack out-of-bounds write vulnerability in the native tiano/EFI decompressor. in uefifirmware/compression/Tiano/Decompress.c, MakeTable does not validate that bit-length values read from the compressed bitstream are within the expected range 0..16. a crafted firmware blob...

PT-2026-56684

UEFI Firmware Parser parses BIOS, Intel ME, and UEFI firmware structures including volumes, file systems, and files. Prior to 1.14, ReadCLen in uefi firmware/compression/Tiano/Decompress.c reads Number from GetBitsSd, CBIT with CBIT = 9 and can obtain 511 entries for the 510-element Sd-mCLen heap...

PT-2026-56683

Name of the Vulnerable Software and Affected Versions UEFI Firmware Parser versions prior to 1.14 Description An issue exists when parsing BIOS, Intel ME, and UEFI firmware structures. The MakeTable function in uefi firmware/compression/Tiano/Decompress.c fails to validate that bit-length values...

SUSE CVE-2026-6100

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...

CVE-2026-6100

A flaw was found in Python's decompression modules, including lzma.LZMADecompressor, bz2.BZ2Decompressor, and gzip.GzipFile. This vulnerability, a use-after-free, can occur if a program attempts to re-use a decompression object after a memory allocation error, especially when the system is...

EUVD-2026-22028

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...

CVE-2026-6100

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...

AZL-83051 CVE-2026-6100 affecting package python3 for versions less than 3.12.9-14

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...

UBUNTU-CVE-2026-6100

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...

CVE-2026-6100

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...

CVE-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...

PSF-2026-18

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...

CVE-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...

CVE-2026-6100

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...