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

Vulnerability from cvelistv5 – Published: 2026-06-08 22:01 – Updated: 2026-06-16 12:23
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.
Severity
8.2 (High)
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-121 - Stack-based buffer overflow
Assigner
PSF
References
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 , < 3.15.0 (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)
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.