SYMBOLCOMMON_NAMEaka. SYNONYMS
win.breach_rat (Back to overview)

BreachRAT

Actor(s): Operation C-Major


This is a backdoor which FireEye call the Breach Remote Administration Tool (BreachRAT), written in C++. The malware name is derived from the hardcoded PDB path found in the RAT: C:\Work\Breach Remote Administration Tool\Release\Client.pdb

References
2016-06-03FireEyeYin Hong Chang, Sudeep Singh
@online{chang:20160603:sends:176f9ab, author = {Yin Hong Chang and Sudeep Singh}, title = {{APT Group Sends Spear Phishing Emails to Indian Government Officials}}, date = {2016-06-03}, organization = {FireEye}, url = {https://www.fireeye.com/blog/threat-research/2016/06/apt_group_sends_spea.html}, language = {English}, urldate = {2019-12-20} } APT Group Sends Spear Phishing Emails to Indian Government Officials
BreachRAT DarkComet Operation C-Major
Yara Rules
[TLP:WHITE] win_breach_rat_auto (20201014 | autogenerated rule brought to you by yara-signator)
rule win_breach_rat_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2020-10-14"
        version = "1"
        description = "autogenerated rule brought to you by yara-signator"
        tool = "yara-signator v0.5.0"
        tool_config = "callsandjumps;datarefs;binvalue"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.breach_rat"
        malpedia_rule_date = "20201014"
        malpedia_hash = "a7e3bd57eaf12bf3ea29a863c041091ba3af9ac9"
        malpedia_version = "20201014"
        malpedia_license = "CC BY-SA 4.0"
        malpedia_sharing = "TLP:WHITE"

    /* DISCLAIMER
     * The strings used in this rule have been automatically selected from the
     * disassembly of memory dumps and unpacked files, using YARA-Signator.
     * The code and documentation is published here:
     * https://github.com/fxb-cocacoding/yara-signator
     * As Malpedia is used as data source, please note that for a given
     * number of families, only single samples are documented.
     * This likely impacts the degree of generalization these rules will offer.
     * Take the described generation method also into consideration when you
     * apply the rules in your use cases and assign them confidence levels.
     */


    strings:
        $sequence_0 = { 8bc8 e8???????? 8d8d5cf5ffff c745fcffffffff e8???????? }
            // n = 5, score = 200
            //   8bc8                 | mov                 ecx, eax
            //   e8????????           |                     
            //   8d8d5cf5ffff         | lea                 ecx, [ebp - 0xaa4]
            //   c745fcffffffff       | mov                 dword ptr [ebp - 4], 0xffffffff
            //   e8????????           |                     

        $sequence_1 = { 8b4004 c7840510ffffff6c114400 8b8510ffffff 8b4804 8d41e8 89840d0cffffff 8d4580 }
            // n = 7, score = 200
            //   8b4004               | mov                 eax, dword ptr [eax + 4]
            //   c7840510ffffff6c114400     | mov    dword ptr [ebp + eax - 0xf0], 0x44116c
            //   8b8510ffffff         | mov                 eax, dword ptr [ebp - 0xf0]
            //   8b4804               | mov                 ecx, dword ptr [eax + 4]
            //   8d41e8               | lea                 eax, [ecx - 0x18]
            //   89840d0cffffff       | mov                 dword ptr [ebp + ecx - 0xf4], eax
            //   8d4580               | lea                 eax, [ebp - 0x80]

        $sequence_2 = { 50 8d8dfcfdffff e8???????? c645fc04 837dbc08 720b }
            // n = 6, score = 200
            //   50                   | push                eax
            //   8d8dfcfdffff         | lea                 ecx, [ebp - 0x204]
            //   e8????????           |                     
            //   c645fc04             | mov                 byte ptr [ebp - 4], 4
            //   837dbc08             | cmp                 dword ptr [ebp - 0x44], 8
            //   720b                 | jb                  0xd

        $sequence_3 = { 51 56 8bf1 8975f0 c706???????? c745fc00000000 837e1000 }
            // n = 7, score = 200
            //   51                   | push                ecx
            //   56                   | push                esi
            //   8bf1                 | mov                 esi, ecx
            //   8975f0               | mov                 dword ptr [ebp - 0x10], esi
            //   c706????????         |                     
            //   c745fc00000000       | mov                 dword ptr [ebp - 4], 0
            //   837e1000             | cmp                 dword ptr [esi + 0x10], 0

        $sequence_4 = { c745fc00000000 56 8bf2 57 85c9 0f84a8000000 8b791c }
            // n = 7, score = 200
            //   c745fc00000000       | mov                 dword ptr [ebp - 4], 0
            //   56                   | push                esi
            //   8bf2                 | mov                 esi, edx
            //   57                   | push                edi
            //   85c9                 | test                ecx, ecx
            //   0f84a8000000         | je                  0xae
            //   8b791c               | mov                 edi, dword ptr [ecx + 0x1c]

        $sequence_5 = { 03cf 8988b4160000 8b55ec 3b9098160000 0f82d5fcffff 8b5dfc 0fb7bb02040000 }
            // n = 7, score = 200
            //   03cf                 | add                 ecx, edi
            //   8988b4160000         | mov                 dword ptr [eax + 0x16b4], ecx
            //   8b55ec               | mov                 edx, dword ptr [ebp - 0x14]
            //   3b9098160000         | cmp                 edx, dword ptr [eax + 0x1698]
            //   0f82d5fcffff         | jb                  0xfffffcdb
            //   8b5dfc               | mov                 ebx, dword ptr [ebp - 4]
            //   0fb7bb02040000       | movzx               edi, word ptr [ebx + 0x402]

        $sequence_6 = { e8???????? 68???????? 8d8ddcf3ffff e8???????? 68???????? }
            // n = 5, score = 200
            //   e8????????           |                     
            //   68????????           |                     
            //   8d8ddcf3ffff         | lea                 ecx, [ebp - 0xc24]
            //   e8????????           |                     
            //   68????????           |                     

        $sequence_7 = { e8???????? 68???????? 8d85ccfaffff c745fc6b000000 50 8bce e8???????? }
            // n = 7, score = 200
            //   e8????????           |                     
            //   68????????           |                     
            //   8d85ccfaffff         | lea                 eax, [ebp - 0x534]
            //   c745fc6b000000       | mov                 dword ptr [ebp - 4], 0x6b
            //   50                   | push                eax
            //   8bce                 | mov                 ecx, esi
            //   e8????????           |                     

        $sequence_8 = { 85f6 7418 8b45a8 8da42400000000 8a0c02 880c13 42 }
            // n = 7, score = 200
            //   85f6                 | test                esi, esi
            //   7418                 | je                  0x1a
            //   8b45a8               | mov                 eax, dword ptr [ebp - 0x58]
            //   8da42400000000       | lea                 esp, [esp]
            //   8a0c02               | mov                 cl, byte ptr [edx + eax]
            //   880c13               | mov                 byte ptr [ebx + edx], cl
            //   42                   | inc                 edx

        $sequence_9 = { e8???????? 68???????? 8d8d54eeffff e8???????? c745fcf8000000 68???????? }
            // n = 6, score = 200
            //   e8????????           |                     
            //   68????????           |                     
            //   8d8d54eeffff         | lea                 ecx, [ebp - 0x11ac]
            //   e8????????           |                     
            //   c745fcf8000000       | mov                 dword ptr [ebp - 4], 0xf8
            //   68????????           |                     

    condition:
        7 of them and filesize < 645120
}
Download all Yara Rules