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Security News, Exploits, and Vulnerabilities.

TA14-300A: Phishing Campaign Linked with “Dyre” Banking Malware

Original release date: October 27, 2014 | Last revised: October 28, 2014

Systems Affected

Microsoft Windows

Overview

Since mid-October 2014, a phishing campaign has targeted a wide variety of recipients while employing the Dyre/Dyreza banking malware. Elements of this phishing campaign vary from target to target including senders, attachments, exploits, themes, and payload(s).[1][2] Although this campaign uses various tactics, the actor’s intent is to entice recipients into opening attachments and downloading malware.

Description

The Dyre banking malware specifically targets sensitive user account credentials. The malware has the ability to capture user login information and send the captured data to malicious actors.[3] Phishing emails used in this campaign often contain a weaponized PDF attachment which attempts to exploit vulnerabilities found in unpatched versions of Adobe Reader.[4][5] After successful exploitation, a user’s system will download Dyre banking malware. All of the major anti-virus vendors have successfully detected this malware prior to the release of this alert.[6]

Please note, the below listing of indicators does not represent all characteristics and indicators for this campaign.

Phishing Email Characteristics:

  • Subject: “Unpaid invoic” (Spelling errors in the subject line are a characteristic of this campaign)
  • Attachment: Invoice621785.pdf

System Level Indicators (upon successful exploitation):

  • Copies itself under C:Windows[RandomName].exe
  • Created a Service named “Google Update Service” by setting the following registry keys:
    • HKLMSYSTEMCurrentControlSetServicesgoogleupdateImagePath: “C:WINDOWSpfdOSwYjERDHrdV.exe”
    • HKLMSYSTEMCurrentControlSetServicesgoogleupdateDisplayName: “Google Update Service”[7]

Impact

A system infected with Dyre banking malware will attempt to harvest credentials for online services, including banking services.

Solution

Users and administrators are recommended to take the following preventive measures to protect their computer networks from phishing campaigns:

US-CERT collects phishing email messages and website locations so that we can help people avoid becoming victims of phishing scams.

You can report phishing to us by sending email to [email protected].

References

Revision History

  • October 27, 2014: Initial Release
  • October 28, 2014: Added Reference 7 in Description Section

This product is provided subject to this Notification and this Privacy & Use policy.

TA14-295A: Crypto Ransomware

Original release date: October 22, 2014 | Last revised: October 24, 2014

Systems Affected

Microsoft Windows

Overview

Ransomware is a type of malicious software (malware) that infects a computer and restricts access to it until a ransom is paid to unlock it. This Alert is the result of Canadian Cyber Incident Response Centre (CCIRC) analysis in coordination with the United States Department of Homeland Security (DHS) to provide further information about crypto ransomware, specifically to:

  • Present its main characteristics, explain the prevalence of ransomware, and the proliferation of crypto ransomware variants; and
  • Provide prevention and mitigation information.

Description

WHAT IS RANSOMWARE?

Ransomware is a type of malware that infects a computer and restricts a user’s access to the infected computer. This type of malware, which has now been observed for several years, attempts to extort money from victims by displaying an on-screen alert. These alerts often state that their computer has been locked or that all of their files have been encrypted, and demand that a ransom is paid to restore access. This ransom is typically in the range of $100–$300 dollars, and is sometimes demanded in virtual currency, such as Bitcoin.

Ransomware is typically spread through phishing emails that contain malicious attachments and drive-by downloading. Drive-by downloading occurs when a user unknowingly visits an infected website and malware is downloaded and installed without their knowledge. Crypto ransomware, a variant that encrypts files, is typically spread through similar methods, and has been spread through Web-based instant messaging applications.

WHY IS IT SO EFFECTIVE?

The authors of ransomware instill fear and panic into their victims, causing them to click on a link or pay a ransom, and inevitably become infected with additional malware, including messages similar to those below:

  • “Your computer has been infected with a virus. Click here to resolve the issue.”
  • “Your computer was used to visit websites with illegal content. To unlock your computer, you must pay a $100 fine.”
  • “All files on your computer have been encrypted. You must pay this ransom within 72 hours to regain access to your data.”

PROLIFERATION OF VARIANTS

In 2012, Symantec, using data from a command and control (C2) server of 5,700 computers compromised in one day, estimated that approximately 2.9 percent of those compromised users paid the ransom. With an average ransom of $200, this meant malicious actors profited $33,600 per day, or $394,400 per month, from a single C2 server. These rough estimates demonstrate how profitable ransomware can be for malicious actors.

This financial success has likely led to a proliferation of ransomware variants. In 2013, more destructive and lucrative ransomware variants were introduced including Xorist, CryptorBit, and CryptoLocker. Some variants encrypt not just the files on the infected device but also the contents of shared or networked drives. These variants are considered destructive because they encrypt user’s and organization’s files, and render them useless until criminals receive a ransom.

Additional variants observed in 2014 included CryptoDefense and Cryptowall, which are also considered destructive. Reports indicate that CryptoDefense and Cryptowall share the same code, and that only the name of malware itself is different. Similar to CryptoLocker, these variants also encrypt files on the local computer, shared network files, and removable media.

LINKS TO OTHER TYPES OF MALWARE

Systems infected with ransomware are also often infected with other malware. In the case of CryptoLocker, a user typically becomes infected by opening a malicious attachment from an email. This malicious attachment contains Upatre, a downloader, which infects the user with GameOver Zeus. GameOver Zeus is a variant of the Zeus Trojan that steals banking information and is also used to steal other types of data. Once a system is infected with GameOver Zeus, Upatre will also download CryptoLocker. Finally, CryptoLocker encrypts files on the infected system, and requests that a ransom be paid.

The close ties between ransomware and other types of malware were demonstrated through the recent botnet disruption operation against GameOver Zeus, which also proved effective against CryptoLocker. In June 2014, an international law enforcement operation successfully weakened the infrastructure of both GameOver Zeus and CryptoLocker.

Impact

Ransomware doesn’t only target home users; businesses can also become infected with ransomware, which can have negative consequences, including:

  • Temporary or permanent loss of sensitive or proprietary information;
  • Disruption to regular operations;
  • Financial losses incurred to restore systems and files; and
  • Potential harm to an organization’s reputation.

Paying the ransom does not guarantee the encrypted files will be released; it only guarantees that the malicious actors receive the victim’s money, and in some cases, their banking information. In addition, decrypting files does not mean the malware infection itself has been removed.

Solution

Infections can be devastating to an individual or organization, and recovery can be a difficult process that may require the services of a reputable data recovery specialist.

US-CERT and CCIRC recommend users and administrators take the following preventive measures to protect their computer networks from ransomware infection:

  • Perform regular backups of all critical information to limit the impact of data or system loss and to help expedite the recovery process. Ideally, this data should be kept on a separate device, and backups should be stored offline.
  • Maintain up-to-date anti-virus software.
  • Keep your operating system and software up-to-date with the latest patches.
  • Do not follow unsolicited web links in email. Refer to the Security Tip Avoiding Social Engineering and Phishing Attacks for more information on social engineering attacks.
  • Use caution when opening email attachments. For information on safely handling email attachments, see Recognizing and Avoiding Email Scams.
  • Follow safe practices when browsing the web. See Good Security Habits and Safeguarding Your Data for additional details.

Individuals or organizations are not encouraged to pay the ransom, as this does not guarantee files will be released. Report instances of fraud to the FBI at the Internet Crime Complaint Center or contact the CCIRC .

References

Revision History

  • October 22, 2014: Initial Release
  • October 24, 2014: Minor edit to the reference section

This product is provided subject to this Notification and this Privacy & Use policy.

Android NFC hack allow users to have free rides in public transportation

More and more people keep talking about the feature of payments via NFC. The problem in this particular case is that somebody reversed the “Tarjeta BIP!” cards and found a means to re-charge them for free.

TA14-290A: SSL 3.0 Protocol Vulnerability and POODLE Attack

Original release date: October 17, 2014 | Last revised: December 10, 2014

Systems Affected

All systems and applications utilizing the Secure Socket Layer (SSL) 3.0 with cipher-block chaining (CBC) mode ciphers may be vulnerable. However, the POODLE (Padding Oracle On Downgraded Legacy Encryption) attack demonstrates this vulnerability using web browsers and web servers, which is one of the most likely exploitation scenarios.

Some Transport Layer Security (TLS) implementations are also vulnerable to the POODLE attack.

Overview

US-CERT is aware of a design vulnerability found in the way SSL 3.0 handles block cipher mode padding. The POODLE attack demonstrates how an attacker can exploit this vulnerability to decrypt and extract information from inside an encrypted transaction.

Description

The SSL 3.0 vulnerability stems from the way blocks of data are encrypted under a specific type of encryption algorithm within the SSL protocol. The POODLE attack takes advantage of the protocol version negotiation feature built into SSL/TLS to force the use of SSL 3.0 and then leverages this new vulnerability to decrypt select content within the SSL session. The decryption is done byte by byte and will generate a large number of connections between the client and server.

While SSL 3.0 is an old encryption standard and has generally been replaced by TLS, most SSL/TLS implementations remain backwards compatible with SSL 3.0 to interoperate with legacy systems in the interest of a smooth user experience. Even if a client and server both support a version of TLS the SSL/TLS protocol suite allows for protocol version negotiation (being referred to as the “downgrade dance” in other reporting). The POODLE attack leverages the fact that when a secure connection attempt fails, servers will fall back to older protocols such as SSL 3.0. An attacker who can trigger a connection failure can then force the use of SSL 3.0 and attempt the new attack. [1]

Two other conditions must be met to successfully execute the POODLE attack: 1) the attacker must be able to control portions of the client side of the SSL connection (varying the length of the input) and 2) the attacker must have visibility of the resulting ciphertext. The most common way to achieve these conditions would be to act as Man-in-the-Middle (MITM), requiring a whole separate form of attack to establish that level of access.

These conditions make successful exploitation somewhat difficult. Environments that are already at above-average risk for MITM attacks (such as public WiFi) remove some of those challenges.

On December 8, 2014, it was publicly reported [2,3,4] that some TLS implementations are also vulnerable to the POODLE attack.

Impact

The POODLE attack can be used against any system or application that supports SSL 3.0 with CBC mode ciphers. This affects most current browsers and websites, but also includes any software that either references a vulnerable SSL/TLS library (e.g. OpenSSL) or implements the SSL/TLS protocol suite itself. By exploiting this vulnerability in a likely web-based scenario, an attacker can gain access to sensitive data passed within the encrypted web session, such as passwords, cookies and other authentication tokens that can then be used to gain more complete access to a website (impersonating that user, accessing database content, etc.).

Solution

There is currently no fix for the vulnerability SSL 3.0 itself, as the issue is fundamental to the protocol; however, disabling SSL 3.0 support in system/application configurations is the most viable solution currently available.

Some of the same researchers that discovered the vulnerability also developed a fix for one of the prerequisite conditions; TLS_FALLBACK_SCSV is a protocol extension that prevents MITM attackers from being able to force a protocol downgrade. OpenSSL has added support for TLS_FALLBACK_SCSV to their latest versions and recommend the following upgrades: [5]

  • OpenSSL 1.0.1 users should upgrade to 1.0.1j.
  • OpenSSL 1.0.0 users should upgrade to 1.0.0o.
  • OpenSSL 0.9.8 users should upgrade to 0.9.8zc.

Both clients and servers need to support TLS_FALLBACK_SCSV to prevent downgrade attacks.

Other SSL 3.0 implementations are most likely also affected by POODLE. Contact your vendor for details. Additional vendor information may be available in the National Vulnerability Database (NVD) entry for CVE-2014-3566 [6] or in CERT Vulnerability Note VU#577193.[7]

Vulnerable TLS implementations need to be updated. CVE ID assignments and vendor information are also available in the NVD.[8]

References

Revision History

  • October 17, 2014 Initial Release
  • October 20, 2014 Added CERT Vulnerability Note VU#577193 to the Solution section
  • December 10, 2014 Noted newer POODLE variant (CVE-2014-8730)

This product is provided subject to this Notification and this Privacy & Use policy.

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