SYMBOLCOMMON_NAMEaka. SYNONYMS
win.webc2_yahoo (Back to overview)

WebC2-Yahoo

Actor(s): Comment Crew


There is no description at this point.

References
2018MandiantMandiant
@techreport{mandiant:2018:apt1:b76cc4d, author = {Mandiant}, title = {{APT1}}, date = {2018}, institution = {Mandiant}, url = {https://github.com/securitykitten/malware_references/blob/master/Appendix%20C%20(Digital)%20-%20The%20Malware%20Arsenal.pdf}, language = {English}, urldate = {2020-01-13} } APT1
Auriga Biscuit Bouncer Combos CookieBag Dairy GetMail GlooxMail Goggles Hacksfase Helauto Kurton ManItsMe MAPIget MiniASP NewsReels SeaSalt StarsyPound Sword TabMsgSQL Tarsip WebC2-AdSpace WebC2-Ausov WebC2-Bolid WebC2-Cson WebC2-DIV WebC2-GreenCat WebC2-Head WebC2-Kt3 WebC2-Qbp WebC2-Rave WebC2-Table WebC2-UGX WebC2-Yahoo
Yara Rules
[TLP:WHITE] win_webc2_yahoo_auto (20201023 | autogenerated rule brought to you by yara-signator)
rule win_webc2_yahoo_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2020-12-22"
        version = "1"
        description = "autogenerated rule brought to you by yara-signator"
        tool = "yara-signator v0.6.0"
        signator_config = "callsandjumps;datarefs;binvalue"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.webc2_yahoo"
        malpedia_rule_date = "20201222"
        malpedia_hash = "30354d830a29f0fbd3714d93d94dea941d77a130"
        malpedia_version = "20201023"
        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 = { 68???????? 50 50 ff15???????? f7d8 1bc0 }
            // n = 6, score = 100
            //   68????????           |                     
            //   50                   | push                eax
            //   50                   | push                eax
            //   ff15????????         |                     
            //   f7d8                 | neg                 eax
            //   1bc0                 | sbb                 eax, eax

        $sequence_1 = { ff15???????? 59 6a64 e8???????? 59 }
            // n = 5, score = 100
            //   ff15????????         |                     
            //   59                   | pop                 ecx
            //   6a64                 | push                0x64
            //   e8????????           |                     
            //   59                   | pop                 ecx

        $sequence_2 = { 57 895dfc e8???????? 8b7508 56 e8???????? }
            // n = 6, score = 100
            //   57                   | push                edi
            //   895dfc               | mov                 dword ptr [ebp - 4], ebx
            //   e8????????           |                     
            //   8b7508               | mov                 esi, dword ptr [ebp + 8]
            //   56                   | push                esi
            //   e8????????           |                     

        $sequence_3 = { 0faf4dfc 8b00 69c010270000 03c8 4e 8bc1 99 }
            // n = 7, score = 100
            //   0faf4dfc             | imul                ecx, dword ptr [ebp - 4]
            //   8b00                 | mov                 eax, dword ptr [eax]
            //   69c010270000         | imul                eax, eax, 0x2710
            //   03c8                 | add                 ecx, eax
            //   4e                   | dec                 esi
            //   8bc1                 | mov                 eax, ecx
            //   99                   | cdq                 

        $sequence_4 = { 7320 57 e8???????? 56 e8???????? 2bc3 03de }
            // n = 7, score = 100
            //   7320                 | jae                 0x22
            //   57                   | push                edi
            //   e8????????           |                     
            //   56                   | push                esi
            //   e8????????           |                     
            //   2bc3                 | sub                 eax, ebx
            //   03de                 | add                 ebx, esi

        $sequence_5 = { e8???????? 8d8507ffffff be???????? 50 56 e8???????? 6a00 }
            // n = 7, score = 100
            //   e8????????           |                     
            //   8d8507ffffff         | lea                 eax, [ebp - 0xf9]
            //   be????????           |                     
            //   50                   | push                eax
            //   56                   | push                esi
            //   e8????????           |                     
            //   6a00                 | push                0

        $sequence_6 = { f3ab 66ab aa 8d85c8d7ffff }
            // n = 4, score = 100
            //   f3ab                 | rep stosd           dword ptr es:[edi], eax
            //   66ab                 | stosw               word ptr es:[edi], ax
            //   aa                   | stosb               byte ptr es:[edi], al
            //   8d85c8d7ffff         | lea                 eax, [ebp - 0x2838]

        $sequence_7 = { 33c0 833d????????01 0f94c0 40 a3???????? }
            // n = 5, score = 100
            //   33c0                 | xor                 eax, eax
            //   833d????????01       |                     
            //   0f94c0               | sete                al
            //   40                   | inc                 eax
            //   a3????????           |                     

        $sequence_8 = { 89869c841e00 e8???????? 83be9c841e0000 59 750e ff15???????? 8986a0841e00 }
            // n = 7, score = 100
            //   89869c841e00         | mov                 dword ptr [esi + 0x1e849c], eax
            //   e8????????           |                     
            //   83be9c841e0000       | cmp                 dword ptr [esi + 0x1e849c], 0
            //   59                   | pop                 ecx
            //   750e                 | jne                 0x10
            //   ff15????????         |                     
            //   8986a0841e00         | mov                 dword ptr [esi + 0x1e84a0], eax

        $sequence_9 = { 50 ff7510 ff15???????? 83c414 e9???????? 57 e8???????? }
            // n = 7, score = 100
            //   50                   | push                eax
            //   ff7510               | push                dword ptr [ebp + 0x10]
            //   ff15????????         |                     
            //   83c414               | add                 esp, 0x14
            //   e9????????           |                     
            //   57                   | push                edi
            //   e8????????           |                     

    condition:
        7 of them and filesize < 8060928
}
Download all Yara Rules