• Home
  • Cyber Crime
  • Cyber warfare
  • APT
  • Data Breach
  • Deep Web
  • Digital ID
  • Hacking
  • Hacktivism
  • Intelligence
  • Internet of Things
  • Laws and regulations
  • Malware
  • Mobile
  • Reports
  • Security
  • Social Networks
  • Terrorism
  • ICS-SCADA
  • POLICIES
  • Contact me
MUST READ

Cisco removed the backdoor account from its Unified Communications Manager

 | 

U.S. Sanctions Russia's Aeza Group for aiding crooks with bulletproof hosting

 | 

Qantas confirms customer data breach amid Scattered Spider attacks

 | 

CVE-2025-6554 is the fourth Chrome zero-day patched by Google in 2025

 | 

U.S. CISA adds TeleMessage TM SGNL flaws to its Known Exploited Vulnerabilities catalog

 | 

A sophisticated cyberattack hit the International Criminal Court

 | 

Esse Health data breach impacted 263,000 individuals

 | 

Europol dismantles €460M crypto scam targeting 5,000 victims worldwide

 | 

CISA and U.S. Agencies warn of ongoing Iranian cyber threats to critical infrastructure

 | 

U.S. CISA adds Citrix NetScaler flaw to its Known Exploited Vulnerabilities catalog

 | 

Canada bans Hikvision over national security concerns

 | 

Denmark moves to protect personal identity from deepfakes with new copyright law

 | 

Ahold Delhaize data breach affected over 2.2 Million individuals

 | 

Facebook wants access to your camera roll for AI photo edits

 | 

SECURITY AFFAIRS MALWARE NEWSLETTER ROUND 51

 | 

Security Affairs newsletter Round 530 by Pierluigi Paganini – INTERNATIONAL EDITION

 | 

The FBI warns that Scattered Spider is now targeting the airline sector

 | 

LapDogs: China-nexus hackers Hijack 1,000+ SOHO devices for espionage

 | 

Taking over millions of developers exploiting an Open VSX Registry flaw

 | 

OneClik APT campaign targets energy sector with stealthy backdoors

 | 
  • Home
  • Cyber Crime
  • Cyber warfare
  • APT
  • Data Breach
  • Deep Web
  • Digital ID
  • Hacking
  • Hacktivism
  • Intelligence
  • Internet of Things
  • Laws and regulations
  • Malware
  • Mobile
  • Reports
  • Security
  • Social Networks
  • Terrorism
  • ICS-SCADA
  • POLICIES
  • Contact me
  • Home
  • Breaking News
  • Hacking
  • PoC exploit code for critical Realtek RCE flaw released online

PoC exploit code for critical Realtek RCE flaw released online

Pierluigi Paganini August 18, 2022

Exploit code for a critical vulnerability affecting networking devices using Realtek RTL819x system on a chip released online.

The PoC exploit code for a critical stack-based buffer overflow issue, tracked as CVE-2022-27255 (CVSS 9.8), affecting networking devices using Realtek’s RTL819x system on a chip was released online. The issue resides in the Realtek’s SDK for the open-source eCos operating system, it was discovered by researchers from cybersecurity firm Faraday Security

“On Realtek eCos SDK-based routers, the ‘SIP ALG’ module is vulnerable to buffer overflow. The root cause of the vulnerability is insufficient validation on the received buffer, and unsafe calls to strcpy. The ‘SIP ALG’ module calls strcpy to copy some contents of SIP packets to a predefined fixed buffer and does not check the length of the copied contents.” reads the advisory published by Realtek, which published the issue in March 2022. “A remote attacker can exploit the vulnerability through a WAN interface by crafting arguments in SDP data or the SIP header to make a specific SIP packet, and the successful exploitation would cause a crash or achieve the remote code execution.”

Millions of devices, including routers and access points, are exposed to hacking.

The experts (Octavio Gianatiempo, Octavio Galland, Emilio Couto, Javier Aguinaga) disclosed technical details of the flaw at the DEFCON hacker conference last week.

A remote attacker can exploit the flaw to execute arbitrary code without authentication by sending to the vulnerable devices specially crafted SIP packets with malicious SDP data.

The issue is very dangerous because the exploitation doesn’t require user interaction.

The PoC code developed by the experts works against Nexxt Nebula 300 Plus routers.

“This repository contains the materials for the talk “Exploring the hidden attack surface of OEM IoT devices: pwning thousands of routers with a vulnerability in Realtek’s SDK for eCos OS.”, which was presented at DEFCON30.” reads the description provided with the exploit code on GitHub.

The repo includes:

  • analysis: Automated firmware analysis to detect the presence of CVE-2022-27255 (Run analyse_firmware.py).
  • exploits_nexxt: PoC and exploit code. The PoC should work on every affected router, however the exploit code is specific for the Nexxt Nebula 300 Plus router.
  • ghidra_scripts: Vulnerable function call searching script and CVE-2022-27255 detection script.
  • DEFCON: Slide deck & poc video.

Johannes Ullrich, Dean of Research at SANS shared a Snort rule that can be used to detect PoC exploit attempt.

“The rule looks for “INVITE” messages that contain the string “m=audio “. It triggers if there are more than 128 bytes following the string (128 bytes is the size of the buffer allocated by the Realtek SDK) and if none of those bytes is a carriage return. The rule may even work sufficiently well without the last content match. Let me know if you see any errors or improvements.” wrote the expert.

Slides for the DEFCON presentation along with exploits, and a detection script for CVE-2022-27255 are available in this GitHub repository.

Follow me on Twitter: @securityaffairs and Facebook

[adrotate banner=”9″][adrotate banner=”12″]

Pierluigi Paganini

(SecurityAffairs – hacking, Realtek)

[adrotate banner=”5″]

[adrotate banner=”13″]


facebook linkedin twitter

hacking news information security news IT Information Security POC code RCE Realtek Security Affairs Security News

you might also like

Pierluigi Paganini July 02, 2025
Cisco removed the backdoor account from its Unified Communications Manager
Read more
Pierluigi Paganini July 02, 2025
U.S. Sanctions Russia's Aeza Group for aiding crooks with bulletproof hosting
Read more

leave a comment

newsletter

Subscribe to my email list and stay
up-to-date!

    recent articles

    Cisco removed the backdoor account from its Unified Communications Manager

    Security / July 02, 2025

    U.S. Sanctions Russia's Aeza Group for aiding crooks with bulletproof hosting

    Cyber Crime / July 02, 2025

    Qantas confirms customer data breach amid Scattered Spider attacks

    Cyber Crime / July 02, 2025

    CVE-2025-6554 is the fourth Chrome zero-day patched by Google in 2025

    Hacking / July 02, 2025

    U.S. CISA adds TeleMessage TM SGNL flaws to its Known Exploited Vulnerabilities catalog

    Hacking / July 02, 2025

    To contact me write an email to:

    Pierluigi Paganini :
    pierluigi.paganini@securityaffairs.co

    LEARN MORE

    QUICK LINKS

    • Home
    • Cyber Crime
    • Cyber warfare
    • APT
    • Data Breach
    • Deep Web
    • Digital ID
    • Hacking
    • Hacktivism
    • Intelligence
    • Internet of Things
    • Laws and regulations
    • Malware
    • Mobile
    • Reports
    • Security
    • Social Networks
    • Terrorism
    • ICS-SCADA
    • POLICIES
    • Contact me

    Copyright@securityaffairs 2024

    We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. By clicking “Accept All”, you consent to the use of ALL the cookies. However, you may visit "Cookie Settings" to provide a controlled consent.
    Cookie SettingsAccept All
    Manage consent

    Privacy Overview

    This website uses cookies to improve your experience while you navigate through the website. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities...
    Necessary
    Always Enabled
    Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.
    Non-necessary
    Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. It is mandatory to procure user consent prior to running these cookies on your website.
    SAVE & ACCEPT