Overview
The cybersecurity landscape is evolving rapidly, with new threats emerging at a staggering rate. One such threat is the CVE-2025-21485, a severe vulnerability in the processing of INIT and multimode invoke IOCTL calls on FastRPC. The vulnerability stems from a memory corruption issue, which can be exploited to compromise the system or lead to data leakage. Being ubiquitous in many systems, FastRPC’s susceptibility to such a flaw raises significant concerns for users across the globe.
The severity of this vulnerability, combined with its widespread potential impact, underscores the necessity for immediate action. With a CVSS score of 7.8, it poses a substantial risk and needs to be addressed promptly to prevent potential exploitation by malicious actors.
Vulnerability Summary
CVE ID: CVE-2025-21485
Severity: High (CVSS: 7.8)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: System Compromise, Data Leakage
Affected Products
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Product | Affected Versions
FastRPC | All versions prior to 3.0.0
How the Exploit Works
The vulnerability lies in the improper handling of certain IOCTL calls by FastRPC. An attacker can exploit this by sending specially crafted INIT and multimode invoke IOCTL calls to the FastRPC interface. These calls cause memory corruption, enabling the attacker to execute arbitrary code or access sensitive information.
Conceptual Example Code
The following conceptual pseudocode demonstrates how an attacker might exploit the vulnerability:
#include <sys/ioctl.h>
#include <fcntl.h>
int main() {
int fd = open("/dev/fastrpc", O_RDWR);
char payload[4096] = { /* crafted payload causing memory corruption */ };
// INIT IOCTL call
ioctl(fd, FASTRPC_IOCTL_INIT, payload);
// Multimode invoke IOCTL call
ioctl(fd, FASTRPC_IOCTL_INVOKE, payload);
close(fd);
return 0;
}Prevention and Mitigation
The best way to prevent exploitation of this vulnerability is to apply the vendor’s patch. If the patch cannot be applied immediately, using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can offer temporary mitigation. However, these are not foolproof solutions and can only reduce, not eliminate, the risk. Therefore, applying the patch at the earliest opportunity is strongly recommended.