CVE-2021-34981

Linux Kernel Bluetooth CMTP Module Double Free Privilege Escalation Vulnerability

At a glance

Severity
HIGH 7.5
EPSS
EPSS 0.20 % · percentile 10 (2026-10-27)
State
PUBLISHED
Published
Updated
Assigner
zdi
NVD status
Analyzed

Description

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.

Scores

VersionScoreVectorScored by
CVSS 3.0HIGH 7.5CVSS:3.0/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:Hzdi
CVSS 3.1MEDIUM 6.7CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:HNVD · nvd@nist.gov (Primary)
CVSS 3.0HIGH 7.5CVSS:3.0/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:HNVD · zdi-disclosures@trendmicro.com (Secondary)

Weaknesses (CWE)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
Linux · Kernelaffected 4.15.0-118-generic

References

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD