CVE-2021-3640
mediumpriority · track · 28EPSS 0.004 · 31 %ileDEEURUUSEPSS · scored 2026-10-27
A flaw use-after-free in function sco_sock_sendmsg() of the Linux kernel HCI subsystem was found in the way user calls ioct UFFDIO_REGISTER or other way triggers race condition of the call sco_conn_del() together with the call sco_sock_sendmsg() with the expected controllable faulting memory page. A privileged local user could use this flaw to crash the system or escalate their privileges on the system.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.4–7
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (48)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2022-1992Linux Kernel: Schwachstelle ermöglicht Denial of ServiceDeutsch2021-07-22csaf · cert_bundDE
Ein lokaler Angreifer kann eine Schwachstelle im Linux Kernel ausnutzen, um einen Denial of Service Angriff durchzuführen.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (60)
External citations — patches, advisories, analysis.
- https://access.redhat.com/errata/RHSA-2022:7444cnnvd
- https://access.redhat.com/errata/RHSA-2022:7683cnnvd
- https://access.redhat.com/errata/RHSA-2022:7933cnnvd
- https://access.redhat.com/errata/RHSA-2022:8267cnnvd
- https://access.redhat.com/security/cve/CVE-2021-3640cnnvd
- https://bugzilla.redhat.com/show_bug.cgi?id=1980646cnnvd
- https://cxsecurity.com/cveshow/CVE-2021-3640/cnnvd
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/bluetooth/sco.c?h=v5.16&id=99c23da0eed4fd20cae8243f2b51e10e66aa0951cnnvd
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