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How the CVE works:
The vulnerability resides in the NR modem’s baseband processing unit, specifically within the Radio Resource Control (RRC) layer message parsing routine. During the decoding of certain protocol data units (PDUs), such as RRC Connection Setup or Reconfiguration messages, the software fails to validate the size and content of embedded information elements. An attacker can remotely transmit a maliciously crafted RRC message containing an abnormally large or invalid “ue-CapabilityRAT-RequestList” field. This malformed input bypasses length checks, leading to a heap buffer overflow when the modem attempts to copy the data into a fixed-size buffer. The overflow corrupts adjacent critical memory structures, including function pointers and state variables, resulting in a null pointer dereference or an illegal memory access. This triggers a fatal exception in the baseband processor, forcing a full modem subsystem reset and causing a persistent denial of service. The exploit requires no authentication and can be executed from a malicious base station or a nearby radio transmitter, impacting device connectivity without user interaction.
Platform: NR Modem Software
Version: Various versions
Vulnerability: Improper input validation
Severity: Critical
Date: 12/01/2025
Prediction: Q1 2026 patch
What Undercode Say:
Analytics:
strings firmware.bin | grep -i "rrc" radare2 -A firmware.bin dd if=modem.img bs=1 skip=$((0x1234)) count=256 | hexdump -C
// Sample code snippet highlighting missing validation
void process_rrc_message(char data, int len) {
// Missing length check for data[bash]
char buffer[bash];
memcpy(buffer, &data[bash], data[bash]); // Potential overflow
}
How Exploit:
Craft malicious RRC message with oversized IE. Transmit via software-defined radio. Target modem’s cell search procedure. Cause buffer overflow and crash.
Protection from this CVE
Apply vendor patch. Disable vulnerable features. Use input sanitization. Update modem firmware.
Impact:
Remote DoS. Network disruption. Device reboot. Service unavailability.
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Sources:
Reported By: nvd.nist.gov
Extra Source Hub:
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