SYMBOLCOMMON_NAMEaka. SYNONYMS
win.jaff (Back to overview)

Jaff


There is no description at this point.

References
2023-02-14Github (clairelevin)Claire Levin
@online{levin:20230214:writing:acb4846, author = {Claire Levin}, title = {{Writing a decryptor for Jaff ransomware}}, date = {2023-02-14}, organization = {Github (clairelevin)}, url = {https://clairelevin.github.io/malware/2023/02/14/jaff.html}, language = {English}, urldate = {2023-02-21} } Writing a decryptor for Jaff ransomware
Jaff
2020-06-22CERT-FRCERT-FR
@techreport{certfr:20200622:volution:fba1cfa, author = {CERT-FR}, title = {{Évolution De Lactivité du Groupe Cybercriminel TA505}}, date = {2020-06-22}, institution = {CERT-FR}, url = {https://www.cert.ssi.gouv.fr/uploads/CERTFR-2020-CTI-006.pdf}, language = {French}, urldate = {2020-06-24} } Évolution De Lactivité du Groupe Cybercriminel TA505
Amadey AndroMut Bart Clop Dridex FlawedGrace Gandcrab Get2 GlobeImposter Jaff Locky Marap Philadephia Ransom QuantLoader Scarab Ransomware SDBbot ServHelper Silence tRat TrickBot
2020-05-21Intel 471Intel 471
@online{471:20200521:brief:048d164, author = {Intel 471}, title = {{A brief history of TA505}}, date = {2020-05-21}, organization = {Intel 471}, url = {https://intel471.com/blog/a-brief-history-of-ta505}, language = {English}, urldate = {2022-02-14} } A brief history of TA505
AndroMut Bart Dridex FlawedAmmyy FlawedGrace Gandcrab Get2 GlobeImposter Jaff Kegotip Locky Necurs Philadephia Ransom Pony QuantLoader Rockloader SDBbot ServHelper Shifu Snatch TrickBot
2017-05-16Malware Traffic AnalysisBrad Duncan
@online{duncan:20170516:20170516:920d589, author = {Brad Duncan}, title = {{2017-05-16 - MORE EXAMPLES OF MALSPAM PUSHING JAFF RANSOMWARE}}, date = {2017-05-16}, organization = {Malware Traffic Analysis}, url = {http://malware-traffic-analysis.net/2017/05/16/index.html}, language = {English}, urldate = {2020-01-07} } 2017-05-16 - MORE EXAMPLES OF MALSPAM PUSHING JAFF RANSOMWARE
Jaff
2017-05-11ProofpointProofpoint Staff
@online{staff:20170511:jaff:1e6dde7, author = {Proofpoint Staff}, title = {{Jaff - New Ransomware From the Actors Behind the Distribution of Dridex, Locky, and Bart}}, date = {2017-05-11}, organization = {Proofpoint}, url = {https://www.proofpoint.com/us/threat-insight/post/jaff-new-ransomware-from-actors-behind-distribution-of-dridex-locky-bart}, language = {English}, urldate = {2019-12-20} } Jaff - New Ransomware From the Actors Behind the Distribution of Dridex, Locky, and Bart
Jaff
Yara Rules
[TLP:WHITE] win_jaff_auto (20230715 | Detects win.jaff.)
rule win_jaff_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2023-07-11"
        version = "1"
        description = "Detects win.jaff."
        info = "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.jaff"
        malpedia_rule_date = "20230705"
        malpedia_hash = "42d0574f4405bd7d2b154d321d345acb18834a41"
        malpedia_version = "20230715"
        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 = { 894704 8b4608 8d1400 52 6a08 894708 }
            // n = 6, score = 600
            //   894704               | mov                 dword ptr [edi + 4], eax
            //   8b4608               | mov                 eax, dword ptr [esi + 8]
            //   8d1400               | lea                 edx, [eax + eax]
            //   52                   | push                edx
            //   6a08                 | push                8
            //   894708               | mov                 dword ptr [edi + 8], eax

        $sequence_1 = { 6a08 c745c800000000 897dcc c645d001 8945e4 ffd3 50 }
            // n = 7, score = 600
            //   6a08                 | push                8
            //   c745c800000000       | mov                 dword ptr [ebp - 0x38], 0
            //   897dcc               | mov                 dword ptr [ebp - 0x34], edi
            //   c645d001             | mov                 byte ptr [ebp - 0x30], 1
            //   8945e4               | mov                 dword ptr [ebp - 0x1c], eax
            //   ffd3                 | call                ebx
            //   50                   | push                eax

        $sequence_2 = { 8a4d08 80e101 884dfc 8b55fc 52 8d45f0 50 }
            // n = 7, score = 600
            //   8a4d08               | mov                 cl, byte ptr [ebp + 8]
            //   80e101               | and                 cl, 1
            //   884dfc               | mov                 byte ptr [ebp - 4], cl
            //   8b55fc               | mov                 edx, dword ptr [ebp - 4]
            //   52                   | push                edx
            //   8d45f0               | lea                 eax, [ebp - 0x10]
            //   50                   | push                eax

        $sequence_3 = { 7506 c6460c00 eb3f 3c30 7424 3c31 7420 }
            // n = 7, score = 600
            //   7506                 | jne                 8
            //   c6460c00             | mov                 byte ptr [esi + 0xc], 0
            //   eb3f                 | jmp                 0x41
            //   3c30                 | cmp                 al, 0x30
            //   7424                 | je                  0x26
            //   3c31                 | cmp                 al, 0x31
            //   7420                 | je                  0x22

        $sequence_4 = { 8b550c 52 6a00 ffd3 50 ffd6 }
            // n = 6, score = 600
            //   8b550c               | mov                 edx, dword ptr [ebp + 0xc]
            //   52                   | push                edx
            //   6a00                 | push                0
            //   ffd3                 | call                ebx
            //   50                   | push                eax
            //   ffd6                 | call                esi

        $sequence_5 = { 8b5590 52 6a00 ffd7 50 ffd6 53 }
            // n = 7, score = 600
            //   8b5590               | mov                 edx, dword ptr [ebp - 0x70]
            //   52                   | push                edx
            //   6a00                 | push                0
            //   ffd7                 | call                edi
            //   50                   | push                eax
            //   ffd6                 | call                esi
            //   53                   | push                ebx

        $sequence_6 = { c6450b01 782a 8b55f8 8a0416 3c01 }
            // n = 5, score = 600
            //   c6450b01             | mov                 byte ptr [ebp + 0xb], 1
            //   782a                 | js                  0x2c
            //   8b55f8               | mov                 edx, dword ptr [ebp - 8]
            //   8a0416               | mov                 al, byte ptr [esi + edx]
            //   3c01                 | cmp                 al, 1

        $sequence_7 = { 8945ec 895df8 3bf3 0f86da000000 8b45f0 }
            // n = 5, score = 600
            //   8945ec               | mov                 dword ptr [ebp - 0x14], eax
            //   895df8               | mov                 dword ptr [ebp - 8], ebx
            //   3bf3                 | cmp                 esi, ebx
            //   0f86da000000         | jbe                 0xe0
            //   8b45f0               | mov                 eax, dword ptr [ebp - 0x10]

        $sequence_8 = { 8b7df8 8bc7 5f 895604 }
            // n = 4, score = 600
            //   8b7df8               | mov                 edi, dword ptr [ebp - 8]
            //   8bc7                 | mov                 eax, edi
            //   5f                   | pop                 edi
            //   895604               | mov                 dword ptr [esi + 4], edx

        $sequence_9 = { 75f9 2bc1 7444 8d642400 83fe0a 7438 8a8c3570fbffff }
            // n = 7, score = 600
            //   75f9                 | jne                 0xfffffffb
            //   2bc1                 | sub                 eax, ecx
            //   7444                 | je                  0x46
            //   8d642400             | lea                 esp, [esp]
            //   83fe0a               | cmp                 esi, 0xa
            //   7438                 | je                  0x3a
            //   8a8c3570fbffff       | mov                 cl, byte ptr [ebp + esi - 0x490]

    condition:
        7 of them and filesize < 106496
}
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