Security readout for executives and security teams
CVE-2021-3564 is a Linux kernel Bluetooth flaw that can let a local user crash a system by abusing HCI TTY device initialization. It is mainly an availability risk, not a confirmed remote compromise issue, and the provided sources do not show active exploitation. Exposure is most relevant on Linux systems running kernels from 3.13 onward where local users or workloads can interact with Bluetooth HCI TTY attachment paths. The bundle does not identify specific distributions beyond linked Debian and Red Hat references. Handle through normal kernel patch management, with higher priority for multi-user Linux systems, shared servers, and environments where downtime is costly. No source in the bundle supports emergency response for active exploitation. Mitigation focus: Apply kernel security updates from the relevant Linux distribution vendor.; Review Debian LTS updates if running affected Debian kernel packages.; Check Red Hat or vendor guidance for affected supported kernel builds..
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
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ATT&CK lookup starting points
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CWE-415: Exact CWE lookup
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Open ATT&CK lookupCVE-2021-3564 mapping review
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Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://bugzilla.redhat.com/show_bug.cgi?id=1964139CVE reference · x_refsource_MISC
- https://www.openwall.com/lists/oss-security/2021/05/25/1CVE reference · x_refsource_MISC
- [debian-lts-announce] 20210623 [SECURITY] [DLA 2689-1] linux security updateCVE reference · mailing-list, x_refsource_MLIST
- [debian-lts-announce] 20210623 [SECURITY] [DLA 2690-1] linux-4.19 security updateCVE reference · mailing-list, x_refsource_MLIST
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Double Free
Double Free represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.