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The CVE-2024-26924 vulnerability is a use-after-free flaw within the Linux kernel’s Netfilter subsystem, specifically in the nf_tables component. The bug exists in the `nf_tables_deactivate_table()` function. The issue arises when a table is deactivated and its state is set to NFT_TABLE_STATE_DYING. A garbage collection mechanism is then scheduled to free the table’s memory. However, a race condition occurs if a new transaction from userspace, attempting to perform operations on the same table, is processed before the garbage collector runs. This new transaction can find the table in the `DYING` state and incorrectly reactivate it by clearing the state, making the table accessible again. Subsequently, when the garbage collector finally executes, it frees the table memory. This leaves kernel data structures with a dangling pointer to the now-freed table object. Any further operations through this pointer lead to a use-after-free condition, potentially corrupting kernel memory and allowing for arbitrary code execution with kernel privileges.
Platform: Linux Kernel
Version: Specific versions pre-patch
Vulnerability : Use-After-Free
Severity: Critical
date: 2024-05-01
Prediction: 2024-05-15
What Undercode Say:
`cat /proc/version`
`uname -r`
`dmesg | grep -i “fail\|error\|warning”`
`sudo modprobe -r nf_tables` (Not Recommended)
`cat /sys/kernel/debug/kmemleak`
How Exploit:
Craft malicious nf_tables transactions.
Exploit race condition timing.
Leverage memory corruption.
Execute arbitrary kernel code.
Protection from this CVE
Update kernel immediately.
Apply vendor security patches.
Disable unprivileged user namespaces.
Restrict kernel module loading.
Impact:
Kernel memory corruption.
Privilege escalation to root.
System crash and instability.
Full system compromise.
🎯Let’s Practice Exploiting & Learn Patching For Free:
Sources:
Reported By: nvd.nist.gov
Extra Source Hub:
Undercode
