CVE-2021-28691 (GCVE-0-2021-28691)

Vulnerability from cvelistv5 – Published: 2021-06-29 11:30 – Updated: 2024-08-03 21:47
VLAI
Summary
Guest triggered use-after-free in Linux xen-netback A malicious or buggy network PV frontend can force Linux netback to disable the interface and terminate the receive kernel thread associated with queue 0 in response to the frontend sending a malformed packet. Such kernel thread termination will lead to a use-after-free in Linux netback when the backend is destroyed, as the kernel thread associated with queue 0 will have already exited and thus the call to kthread_stop will be performed against a stale pointer.
Severity
No CVSS data available.
CWE
  • unknown
Assigner
XEN
References
Impacted products
Vendor Product Version
Linux Linux Unknown: unspecified , < 4.12 (custom)
Affected: 5.5.0 , < unspecified (custom)
Unaffected: next of 5.12.2 , < unspecified (custom)
Create a notification for this product.
Credits
{'credit_data': {'description': {'description_data': [{'lang': 'eng', 'value': 'This issue was discovered by Michael Brown of iPXE and diagnosed by\nOlivier Benjamin, Michael Kurth and Martin Mazein of AWS.'}]}}}
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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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  • 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.