CVE-2026-9669 (GCVE-0-2026-9669)

Vulnerability from cvelistv5 – Published: 2026-06-08 22:01 – Updated: 2026-07-07 16:59
VLAI
Title
bz2.BZ2Decompressor reuse after error can cause a stack buffer overflow
Summary
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. This could crash the process when processing untrusted data.
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-121 - Stack-based buffer overflow
Assigner
PSF
Impacted products
Vendor Product Version
Python Software Foundation CPython Affected: 0 , < 3.13.14 (python)
Affected: 3.14.0 , < 3.14.6 (python)
Affected: 3.15.0a1 , < 3.15.0b3 (python)
Create a notification for this product.
Credits
Bitshift (https://github.com/TheShiftedBit) Emma Smith (https://github.com/emmatyping) Stan Ulbrych (https://github.com/StanFromIreland) Serhiy Storchaka (https://github.com/serhiy-storchaka)
Show details on NVD website

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