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CVE-2021-3679 is a denial-of-service vulnerability in the Linux kernel tracing subsystem prior to 5.14-rc3. A stale value used by the ring-buffer empty-state logic can cause a trace-pipe reader to remain indefinitely in an event-polling loop. The affected task stays in the running state, consumes CPU and power resources, and may not be terminable through normal signals, including SIGKILL.
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1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos.
This repository provides a proof-of-concept (POC) exploit for a logic bug in the Linux kernel's ring buffer handling, specifically in the `rb_per_cpu_empty` logic, affecting kernel versions 3.10 to 5.14-rc1. The main exploit is a bash script (`rbdetonate`) that compiles and uses a C helper program (`rbwrite`) to generate trace events and manipulate the kernel's tracing ring buffer via uprobe. The exploit requires root privileges and a system with tracefs mounted and userspace tracing enabled. If successful, it causes a process to enter an unkillable busy loop in kernel space, demonstrating a denial-of-service condition. The repository contains four files: a bash exploit script, a README with detailed instructions and background, a COPYING file with the GPL license, and a .gitignore. The exploit is local and does not target remote systems. Key fingerprintable endpoints include several files under `/sys/kernel/debug/tracing` used for kernel tracing and event configuration.
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3 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
Linux kernel denial-of-service vulnerability in rb_per_cpu_empty().
Denial-of-service vulnerability in the Linux kernel rb_per_cpu_empty function.
A Linux kernel tracing ring-buffer flaw that can cause tracing_read_pipe() to enter an uninterruptible infinite event-polling loop, resulting in denial of service and excessive power consumption. Exploitation requires privileged tracefs control.
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Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.