Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c15abe6d743e759…

MALICIOUS

PDF

68.3 KB Created: 2021-04-09 17:47:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 8354225b0c42d9b7cb533a193b795d42 SHA-1: 353a70f170c9f59e8bbf7d053aa50a113540cc9d SHA-256: 8c15abe6d743e75935904dfc9b30262e28deca1c28cac4c81003eca8bb4266b7
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm or SEO manipulation tactic. ClamAV and ML heuristics identify it as malicious, likely a phishing or trojan delivery mechanism. The embedded URLs suggest an attempt to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://nipisod.ru/strik?utm_term=circle+theorems+rules+sheet+tes PDF link annotation
    • http://bexemusu.mypressonline.com/plantronics_voyager_legend_connect_to_computer.pdfIn PDF document text
    • https://jufufowepum.weebly.com/uploads/1/3/5/3/135348100/0e00b87509ceb9.pdfIn PDF document text
    • https://lozexisivebuzon.weebly.com/uploads/1/3/4/7/134702594/f77ee48ecff2.pdfIn PDF document text
    • https://zexaloguf.weebly.com/uploads/1/3/4/5/134576330/f53fb4aeb04ed32.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4426696/normal_5fcefb7d6768d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446782/normal_604234dd60bbb.pdfIn PDF document text
    • https://demozopadusil.weebly.com/uploads/1/3/2/8/132816094/lutuwanirujudufopori.pdfIn PDF document text
    • https://vetepoxep.weebly.com/uploads/1/3/5/3/135302771/zenagefexafeva-tidetugerag.pdfIn PDF document text
    • http://dotavulilego.mypressonline.com/47112637442.pdfIn PDF document text
    • http://liwitesuzemumex.sportsontheweb.net/29316336448.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://rozibata.epizy.com/kosafagu.pdfIn PDF document text
    • http://domuromu.atwebpages.com/biomagnetismo_pares_por_enfermedad.pdfIn PDF document text
    • http://tujefuguxofela.rf.gd/80193125636.pdfIn PDF document text
    • http://woxutubutofewev.rf.gd/princeton_review_cracking_the_new_sat.pdfIn PDF document text
    • https://a80c0318-1640-4d50-a016-df037fc402b9.filesusr.com/ugd/895bef_cc06a40447534650956067e03c662dfc.pdf?index=trueIn PDF document text
    • http://gitojaxekeveki.onlinewebshop.net/58790321319.pdfIn PDF document text
    • https://592908bf-dd96-48cc-88d9-ffebbdd10d84.filesusr.com/ugd/f34823_12bf9944e95f45018cd1520668fe7ae0.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/zurovajij/hull_options_futures_and_other_derivatives_10th_edition_solutions.pdfIn PDF document text
    • http://tesefosibat.rf.gd/dalilovatifitum.pdfIn PDF document text
    • https://cbb9655c-b60d-4095-8c1c-bb5f9a2903c5.filesusr.com/ugd/4dd980_bb7799eb808c464a87a3382a4028ae23.pdf?index=trueIn PDF document text
    • https://59bb578d-b312-442a-858b-1a1a54b18a6c.filesusr.com/ugd/c79b1c_1c363da14bc84828ad7c3823d2744fdb.pdf?index=trueIn PDF document text
    • http://wetosevezobesof.rf.gd/fukibazigobugafanas.pdfIn PDF document text
    • https://s3.amazonaws.com/vokeri/ics_200_c_answers_2019.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d1e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1E8 4732 bytes
SHA-256: bf331f7a507516ad8a0512fc3d1b7758370efa60d51d868dd98dc3085529d551
font_01_sfnt_off0000e1cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1CF 10028 bytes
SHA-256: a8c613642054855d4b45e096ddbdd965f12ee5d8c686d294ba0ebd6123bf8b06