CVE-2021-34981 (GCVE-0-2021-34981)

Vulnerability from cvelistv5 – Published: 2024-05-07 22:54 – Updated: 2024-08-04 00:26
VLAI
Title
Linux Kernel Bluetooth CMTP Module Double Free Privilege Escalation Vulnerability
Summary
Linux Kernel Bluetooth CMTP Module Double Free Privilege Escalation Vulnerability. This vulnerability allows local attackers to escalate privileges on affected installations of Linux Kernel. An attacker must first obtain the ability to execute high-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the CMTP module. The issue results from the lack of validating the existence of an object prior to performing further free operations on the object. An attacker can leverage this vulnerability to escalate privileges and execute code in the context of the kernel. Was ZDI-CAN-11977.
Severity
7.5 (High)
CVSS:3.0/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
Assigner
zdi
References
Impacted products
Vendor Product Version
Linux Kernel Affected: 4.15.0-118-generic
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linux kernel Affected: 4.15.0-118-generic
    cpe:2.3:a:linux:kernel:4.15.0-118-generic:*:*:*:*:*:*:*
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Date Public
2021-10-26 10:10
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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.