Cyber Resilience

CVE-2021-3347

HighPublic PoC

Published: 29 January 2021

Published
29 January 2021
Modified
25 February 2026
KEV Added
—
Patch
—
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 0.0020 42.1th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-3347 is a high-severity Use After Free (CWE-416) vulnerability in Debian Debian Linux. Its CVSS base score is 7.8 (High).

Operationally, ranked at the 42.1th 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

An issue was discovered in the Linux kernel through 5.10.11. PI futexes have a kernel stack use-after-free during fault handling, allowing local users to execute code in the kernel, aka CID-34b1a1ce1458.

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
≤ 5.10.11
debian
debian linux
10.0, 9.0
fedoraproject
fedora
32, 33

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