CVE-2021-33909

PoC ×2—

CVSS 3.1

7.8 high

EPSS

10%p95

Published

Jul 20, 2021 (Jul 20, 2021)

Modified

Jun 17, 2026

Description

fs/seq_file.c in the Linux kernel 3.16 through 5.13.x before 5.13.4 does not properly restrict seq buffer allocations, leading to an integer overflow, an Out-of-bounds Write, and escalation to root by an unprivileged user, aka CID-8cae8cd89f05.

Vendors: linux fedoraproject debian netapp oracle sonicwall
Products: linux kernel, fedora, debian linux, hci management node, solidfire, communications session border controller, sma1000 firmware
Weakness: CWE-190, CWE-787
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

NVD CVE.org GitHub PoCs EPSS (9.7%)

In the news7 stories

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Researchers flag 7-years-old privilege escalation flaw in Linux kernel (CVE-2021-33909)

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