CVE-2026-3298 (GCVE-0-2026-3298)

Vulnerability from cvelistv5 – Published: 2026-04-21 14:45 – Updated: 2026-08-13 00:27
VLAI
Title
Out-of-bounds write in Windows asyncio.ProacterEventLoop.sock_recvfrom_into() when using nbytes
Summary
The method "sock_recvfrom_into()" of "asyncio.ProacterEventLoop" (Windows only) was missing a boundary check for the data buffer when using nbytes parameter. This allowed for an out-of-bounds buffer write if data was larger than the buffer size. Non-Windows platforms are not affected.
Severity
8.8 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-21 19:15 UTC
CWE
Assigner
PSF CNA under the mitre root
CNA scorecard B 80/100 over 27 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Python Software Foundation CPython Affected: 0 , < 3.11.16 (python)
Affected: 3.12.0 , < 3.12.14 (python)
Affected: 3.13.0 , < 3.13.14 (python)
Affected: 3.14.0a1 , < 3.14.5rc1 (python)
Affected: 3.15.0a1 , < 3.15.0b1 (python)
guessed Create a notification for this product.
Credits
GGAutomaton (https://github.com/GGAutomaton) Victor Stinner (https://github.com/vstinner) Seth Larson (https://github.com/sethmlarson)
Show details on NVD website
To clipboard 

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        "assignerOrgId": "28c92f92-d60d-412d-b760-e73465c3df22",
        "assignerShortName": "PSF",
        "cveId": "CVE-2026-3298",
        "datePublished": "2026-04-21T14:45:01.919Z",
        "dateReserved": "2026-02-26T20:12:47.041Z",
        "dateUpdated": "2026-08-13T00:27:55.667Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



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Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

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

Author Source Type Date Other

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.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.