• 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

Italian police arrested a Chinese national suspected of cyberespionage on a U.S. warrant

 | 

U.S. CISA adds MRLG, PHPMailer, Rails Ruby on Rails, and Synacor Zimbra Collaboration Suite flaws to its Known Exploited Vulnerabilities catalog

 | 

IT Worker arrested for selling access in $100M PIX cyber heist

 | 

New Batavia spyware targets Russian industrial enterprises

 | 

Taiwan flags security risks in popular Chinese apps after official probe

 | 

U.S. CISA adds Google Chromium V8 flaw to its Known Exploited Vulnerabilities catalog

 | 

Hunters International ransomware gang shuts down and offers free decryption keys to all victims

 | 

SECURITY AFFAIRS MALWARE NEWSLETTER ROUND 52

 | 

Security Affairs newsletter Round 531 by Pierluigi Paganini – INTERNATIONAL EDITION

 | 

North Korea-linked threat actors spread macOS NimDoor malware via fake Zoom updates

 | 

Critical Sudo bugs expose major Linux distros to local Root exploits

 | 

Google fined $314M for misusing idle Android users' data

 | 

A flaw in Catwatchful spyware exposed logins of +62,000 users

 | 

China-linked group Houken hit French organizations using zero-days

 | 

Cybercriminals Target Brazil: 248,725 Exposed in CIEE One Data Breach

 | 

Europol shuts down Archetyp Market, longest-running dark web drug marketplace

 | 

Kelly Benefits data breach has impacted 550,000 people, and the situation continues to worsen as the investigation progresses

 | 

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

 | 
  • 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
  • Cyber Crime
  • Hacking
  • Security
  • DNS cache poisoning attacks to steal emails are reality

DNS cache poisoning attacks to steal emails are reality

Pierluigi Paganini September 13, 2014

CERT warns that DNS Cache Poisoning attacks could be used also to hijack email to a rogue server and not only to divert the Internet traffic.

DNS attacks are very popular in hacking community, they could be run by cyber criminals and state-sponsored hackers for various purposes, including cyber espionage and financially motivated attacks.

A DNS is a critical component in a network because it is responsible for the translation of logical names into IP addresses, but an attacker could hit DNS servers to force to return an incorrect IP address and divert traffic to another computer managed by bad actors.

Recently we have assisted different cases of DNS spoofing or cache poisoning attacks, in which hackers redirect the traffic of a legitimate website to a bogus one with serious consequences.

But DNS is also a crucial component for many other Internet protocols, including email that use DNS responses to determine the final recipient of the email.

Virus Bulletin has recently published an interesting post on DNS poisoning attacks used to steal users’ emails in which the experts explained the role of DNS in mailing systems:

“When an email is sent over the Internet, the sender’s mail server needs to find the recipient’s mail server. This takes two DNS lookups: first, the MX record for the recipient’s domain is requested, which returns one or more domains of the inbound mail server. The A record of one of these domains is then requested to find the corresponding IP address.” states the post from Virus Bulletin.

dns attacks email

A threat actor could interfere with the above process, in particular manipulating one of the two responses, can hijack the mail to its server.

Recently CERT/CC researchers Jonathan Spring and Leigh Metcalf have provided the evidence that such attacks are ordinarily conducted by hackers. The researchers have analyzed DNS responses for A records belonging to mail servers of the principal providers, including Gmail, Yahoo! and Hotmail.

“Using our passive DNS data source, we can observe cache poisoning. What we really observe are changes in the answers that are returned for certain domains, but after consulting with various experts, we believe the only behavior these changes indicate is a successful cache poisoning attack.”

How to prevent this kind of attacks?

The CERT/CC researchers mentioned two solutions to prevent this kind of attacks, one at the user side and the other at the server side.

  • At the user level, one should use end-to-end encryption using PGP or S/MIME, of course this solution can only protect the content of the email, but not the routing process.
  • At the server level, it is possible to adopt the DNSSEC, a mechanism to guarantee the integrity of the DNS responses the issue should be solved by DNSSEC, which guarantees the integrity of the DNS responses, unfortunately only a limited number of domains currently deploy DNSSEC.

In the graphic below it is possible to note that only around 0.5% of the .com and .net domains currently support DNSSEC.

dns attacks email DNSSEC diffusion

The experts at CERT highlighted that they ignore the motivation of the attacks neither the threat actors behind them, in the blog post published they also provides the list of the IP addresses involved in the attacks.

Pierluigi Paganini

(Security Affairs – DNS attacks, email)


facebook linkedin twitter

cache poisoning CERT DNS dns attacks DNS spoofing email Hacking PGP Pierluigi Paganini Security Affairs

you might also like

Pierluigi Paganini July 08, 2025
Italian police arrested a Chinese national suspected of cyberespionage on a U.S. warrant
Read more
Pierluigi Paganini July 08, 2025
U.S. CISA adds MRLG, PHPMailer, Rails Ruby on Rails, and Synacor Zimbra Collaboration Suite flaws to its Known Exploited Vulnerabilities catalog
Read more

leave a comment

newsletter

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

    recent articles

    Italian police arrested a Chinese national suspected of cyberespionage on a U.S. warrant

    Intelligence / July 08, 2025

    U.S. CISA adds MRLG, PHPMailer, Rails Ruby on Rails, and Synacor Zimbra Collaboration Suite flaws to its Known Exploited Vulnerabilities catalog

    Hacking / July 08, 2025

    IT Worker arrested for selling access in $100M PIX cyber heist

    Cyber Crime / July 08, 2025

    New Batavia spyware targets Russian industrial enterprises

    Malware / July 07, 2025

    Taiwan flags security risks in popular Chinese apps after official probe

    Security / July 07, 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