CVE-2023-53478
BaseFortify
Publication date: 2025-10-01
Last updated on: 2025-10-02
Assigner: kernel.org
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | From 5.15.160 (inc) to 5.16 (inc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability in the Linux kernel involves a race condition on the 'last_cmd' variable used in synthetic_events tracing. Multiple processes can access 'last_cmd' asynchronously when manipulating synthetic_events nodes simultaneously, leading to use-after-free or double-free errors. This happens because 'last_cmd' can be freed by one process while another process still accesses it. The issue was fixed by adding a mutex ('lastcmd_mutex') to prevent asynchronous access to 'last_cmd'.
How can this vulnerability impact me? :
The vulnerability can cause use-after-free or double-free errors in the Linux kernel's tracing subsystem, which may lead to kernel crashes or instability. This can affect system reliability and potentially be exploited to cause denial of service or other unintended behavior in systems using the affected kernel tracing features.
How can this vulnerability be detected on my network or system? Can you suggest some commands?
This vulnerability can be detected by reproducing the race condition in a KASAN (Kernel Address Sanitizer) environment using two concurrent scripts that write specific byte sequences to /sys/kernel/tracing/synthetic_events. The provided example commands are: Script 1: while :; do echo -n -e '\x88' > /sys/kernel/tracing/synthetic_events; done Script 2: while :; do echo -n -e '\xb0' > /sys/kernel/tracing/synthetic_events; done Running these scripts in different shells can trigger the use-after-free or double-free conditions, which KASAN can detect and report.
What immediate steps should I take to mitigate this vulnerability?
Immediate mitigation involves applying the patch that adds a mutex (lastcmd_mutex) to prevent asynchronous access to the last_cmd variable, thereby avoiding the race conditions leading to use-after-free or double-free. Until the patch is applied, avoid concurrent manipulation of the synthetic_events node by multiple users or processes to reduce the risk of triggering the vulnerability.