Kaspersky Threats — Backdoor.MSIL.Bahma.eg

クラス: Backdoor

バックドアは、悪意のあるユーザーが感染したコンピュータをリモートコントロールできるように設計されています。機能性の面では、バックドアはソフトウェア開発者が設計し配布する多くの管理システムに似ています。これらの種類の悪質なプログラムは、ファイルの送受信、ファイルの起動や削除、メッセージの表示、データの削除、コンピュータの再起動など、感染したコンピュータ上で必要な作業を可能にします。このカテゴリのプログラムは、被害者のコンピュータのグループを結びつけ、ボットネットまたはゾンビネットワークを形成するためです。これにより、悪意のあるユーザーは感染したコンピュータの軍隊を集中管理し、犯罪目的で使用することができます。 Net-Wormのように、ネットワークを介して拡散して他のコンピュータに感染することができるバックドアのグループもあります。違いは、このようなBackdoorは（Net-Wormのように）自動的に広がるのではなく、それらを制御する悪意のあるユーザーからの特別な「コマンド」に限られるということです。

プラットフォーム: MSIL

Common Intermediate Language（旧称Microsoft Intermediate Language、またはMSIL）は、Microsoftが.NET Framework用に開発した中間言語です。 CILコードは、Microsoft Visual Studio（Visual Basic .NET、Visual C ++、Visual C＃など）のすべてのMicrosoft .NETコンパイラによって生成されます。

ファミリー: Backdoor.MSIL.Bahma

No family description

Examples

DF9296432840212456BC4119837CBDDE

Tactics and Techniques: Mitre*

TA0001

Initial Access

The adversary is trying to get into your network. Initial Access consists of techniques that use various entry vectors to gain their initial foothold within a network. Techniques used to gain a foothold include targeted spearphishing and exploiting weaknesses on public-facing web servers. Footholds gained through initial access may allow for continued access, like valid accounts and use of external remote services, or may be limited-use due to changing passwords.

T1566.001

Spearphishing Attachment

Adversaries may send spearphishing emails with a malicious attachment in an attempt to gain access to victim systems. Spearphishing attachment is a specific variant of spearphishing. Spearphishing attachment is different from other forms of spearphishing in that it employs the use of malware attached to an email. All forms of spearphishing are electronically delivered social engineering targeted at a specific individual, company, or industry. In this scenario, adversaries attach a file to the spearphishing email and usually rely upon User Execution to gain execution. Spearphishing may also involve social engineering techniques, such as posing as a trusted source.

TA0002

Execution

The adversary is trying to run malicious code. Execution consists of techniques that result in adversary-controlled code running on a local or remote system. Techniques that run malicious code are often paired with techniques from all other tactics to achieve broader goals, like exploring a network or stealing data. For example, an adversary might use a remote access tool to run a PowerShell script that does Remote System Discovery.

T1204.002

Malicious File

An adversary may rely upon a user opening a malicious file in order to gain execution. Users may be subjected to social engineering to get them to open a file that will lead to code execution. This user action will typically be observed as follow-on behavior from Spearphishing Attachment. Adversaries may use several types of files that require a user to execute them, including .doc, .pdf, .xls, .rtf, .scr, .exe, .lnk, .pif, .cpl, and .reg.

TA0004

Privilege Escalation

The adversary is trying to gain higher-level permissions. Privilege Escalation consists of techniques that adversaries use to gain higher-level permissions on a system or network. Adversaries can often enter and explore a network with unprivileged access but require elevated permissions to follow through on their objectives. Common approaches are to take advantage of system weaknesses, misconfigurations, and vulnerabilities. Examples of elevated access include: SYSTEM/root level, local administrator, user account with admin-like access, user accounts with access to specific system or perform specific function. These techniques often overlap with Persistence techniques, as OS features that let an adversary persist can execute in an elevated context.

T1055.004

Asynchronous Procedure Call

Adversaries may inject malicious code into processes via the asynchronous procedure call (APC) queue in order to evade process-based defenses as well as possibly elevate privileges. APC injection is a method of executing arbitrary code in the address space of a separate live process.

T1134

Access Token Manipulation

Adversaries may modify access tokens to operate under a different user or system security context to perform actions and bypass access controls. Windows uses access tokens to determine the ownership of a running process. A user can manipulate access tokens to make a running process appear as though it is the child of a different process or belongs to someone other than the user that started the process. When this occurs, the process also takes on the security context associated with the new token.

TA0005

Defense Evasion

The adversary is trying to avoid being detected. Defense Evasion consists of techniques that adversaries use to avoid detection throughout their compromise. Techniques used for defense evasion include uninstalling/disabling security software or obfuscating/encrypting data and scripts. Adversaries also leverage and abuse trusted processes to hide and masquerade their malware. Other tactics' techniques are cross-listed here when those techniques include the added benefit of subverting defenses.

T1055.004

Asynchronous Procedure Call

T1055.012

Process Hollowing

Adversaries may inject malicious code into suspended and hollowed processes in order to evade process-based defenses. Process hollowing is a method of executing arbitrary code in the address space of a separate live process.

T1134

Access Token Manipulation