Cyber Resilience

CVE-2021-33034

HighPublic PoC

Published: 14 May 2021

Published
14 May 2021
Modified
21 November 2024
KEV Added
—
Patch
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CVSS Score v3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0013 33.0th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-33034 is a high-severity Use After Free (CWE-416) vulnerability in Linux Linux Kernel. Its CVSS base score is 7.8 (High).

Operationally, ranked at the 33.0th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

In the Linux kernel before 5.12.4, net/bluetooth/hci_event.c has a use-after-free when destroying an hci_chan, aka CID-5c4c8c954409. This leads to writing an arbitrary value.

CWE(s)
CWE-416

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

linux
linux kernel
≤ 5.12.4
fedoraproject
fedora
34
debian
debian linux
9.0

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SI-16 Memory Protection
addresses: CWE-416

Use-after-free exploits that achieve arbitrary code execution are blocked or significantly hardened by non-executable pages and ASLR.

References