CVE-2025-1290: High Severity Race Condition Use-After-Free Vulnerability in Kernel 5.4 on ChromeOS

Overview

The cybersecurity landscape is fraught with a multitude of vulnerabilities, and one that is causing significant concern is CVE-2025-1290. This high severity vulnerability exists within ChromeOS’s Kernel 5.4, specifically in the virtio_transport_space_update function. As it’s a race condition Use-After-Free vulnerability, it has far-reaching implications, potentially affecting a broad range of systems and devices running on the ChromeOS platform. This vulnerability matters because it can lead to system compromise or data leakage, creating a potential goldmine for malicious actors seeking to exploit such weaknesses.

Vulnerability Summary

CVE ID: CVE-2025-1290
Severity: High (CVSS Score: 8.1)
Attack Vector: Local Network
Privileges Required: Low
User Interaction: None
Impact: Potential system compromise or data leakage

Affected Products

Product | Affected Versions

ChromeOS | Kernel 5.4

How the Exploit Works

The vulnerability stems from a race condition in the virtio_transport_space_update function within the Kernel 5.4 on ChromeOS. A race condition is a situation where the behavior of a system depends on the relative timing of events, such as the ordering of read/write operations. The issue arises when concurrent allocation and freeing of the virtio_vsock_sock structure during an AF_VSOCK connect syscall occur before a worker thread accesses it. This leads to a dangling pointer, which can potentially lead to kernel code execution.

Conceptual Example Code

This is a conceptual example of how the vulnerability might be exploited. It is important to note that this is a high-level representation and may not reflect the actual code used in a real-world exploit.

#include <stdlib.h>
#include <pthread.h>
typedef struct {
char *pointer;
} virtio_vsock_sock;
void *thread1(void *vsock) {
// Simulate allocation and freeing of vsock structure
((virtio_vsock_sock*)vsock)->pointer = malloc(128);
free(((virtio_vsock_sock*)vsock)->pointer);
return NULL;
}
void *thread2(void *vsock) {
// Simulate worker thread accessing vsock structure
// after it has been freed
if (((virtio_vsock_sock*)vsock)->pointer != NULL) {
// Insert malicious code here
}
return NULL;
}
int main() {
pthread_t t1, t2;
virtio_vsock_sock vsock;
pthread_create(&t1, NULL, thread1, &vsock);
pthread_create(&t2, NULL, thread2, &vsock);
pthread_join(t1, NULL);
pthread_join(t2, NULL);
return 0;
}

This code simulates the scenario where a worker thread tries to access the virtio_vsock_sock structure after it has already been freed. If the timing of these operations is manipulated in just the right way, the `thread2` function can potentially execute arbitrary code in the kernel space.

Mitigation

To mitigate the risks associated with this vulnerability, users are advised to apply the vendor patch as soon as it becomes available. In the meantime, using a Web Application Firewall (WAF) or an Intrusion Detection System (IDS) can provide a temporary mitigation. These systems can help identify and block attempts to exploit the vulnerability, providing an additional layer of security while the patch is being deployed.