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CVE-2021-20257 (GCVE-0-2021-20257)

Vulnerability from cvelistv5 – Published: 2022-03-16 14:12 – Updated: 2024-08-03 17:37
VLAI
Summary
An infinite loop flaw was found in the e1000 NIC emulator of the QEMU. This issue occurs while processing transmits (tx) descriptors in process_tx_desc if various descriptor fields are initialized with invalid values. This flaw allows a guest to consume CPU cycles on the host, resulting in a denial of service. The highest threat from this vulnerability is to system availability.
Severity
6.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
n/a QEMU Affected: Fixed-In v6.2.0
Show details on NVD website
To clipboard 

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      "cve": "CVE-2021-20257",
      "id": "CVE-2021-20257",
      "initial_release_date": "2021-02-10T00:00:00+00:00",
      "product_status:fixed": "1786",
      "product_status:known_affected": "81",
      "product_status:known_not_affected": "5",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "QEMU: net: e1000: infinite loop while processing transmit descriptors",
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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

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.


Detection rules are retrieved from Rulezet.