Malicious PDF — malware analysis report

Static analysis result for SHA-256 51905045191a50e3…

MALICIOUS

PDF

92.1 KB Created: 2021-03-04 15:37:04 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: 027cdba57195a79dc5d8edbb46bb9750 SHA-1: e945cc2a5772a4d62f644c7086a7f178b6c5adcb SHA-256: 51905045191a50e3fc28f5aee519a939784fca78cdcf44e52460abf743a2e77d
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous external links, identified as a link farm, with one prominent URL pointing to 'fokemale.ru'. The heuristic 'PDF_SEO_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly indicate a malicious intent to redirect users to a network of sites. The ML classifier and ClamAV detection further support the malicious nature of this PDF, classifying it as a phishing or trojan variant.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://fokemale.ru/strik?utm_term=practice+sat+writing+section+pdf PDF link annotation
    • https://xejukogafowoje.weebly.com/uploads/1/3/2/6/132682905/nafodudozumi-jazebi.pdfIn PDF document text
    • https://cdn.sqhk.co/zosiwutu/Ziwiahb/pivelinokinebed.pdfIn PDF document text
    • https://puwulafu.weebly.com/uploads/1/3/5/3/135329465/fexitilirosafo-kerumegeru.pdfIn PDF document text
    • https://sojagifuwolu.weebly.com/uploads/1/3/4/6/134689160/lobinawuxitalu-fuwun.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4412889/normal_5ffaac1c4b265.pdfIn PDF document text
    • https://cdn.sqhk.co/fekebazi/ijjjgmb/nails_salons_open_late_today.pdfIn PDF document text
    • https://cdn.sqhk.co/joxomawezu/7wLhijd/42357922968.pdfIn PDF document text
    • https://kelebewo.weebly.com/uploads/1/3/4/3/134359650/popupag.pdfIn PDF document text
    • https://cdn.sqhk.co/jinubodilev/hh6ihY2/passport_photo_maker_free_key.pdfIn PDF document text
    • https://simefaburiso.weebly.com/uploads/1/3/0/8/130814859/97b3c36.pdfIn PDF document text
    • https://xijapesulole.weebly.com/uploads/1/3/4/5/134588017/207f4.pdfIn PDF document text
    • https://detosujedeke.weebly.com/uploads/1/3/4/3/134371576/4618506.pdfIn PDF document text
    • https://tinonerapize.weebly.com/uploads/1/3/5/3/135349756/e7ba64bf927f.pdfIn PDF document text
    • https://waxevinibiwe.weebly.com/uploads/1/3/0/9/130969944/8605554.pdfIn PDF document text
    • https://cdn.sqhk.co/vixemujomu/kgdNWge/star_wars_flight_simulator_pc_games.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4407318/normal_5ff2237b17fd0.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://8ed62699-7d02-4439-b935-4286882ef7d4.filesusr.com/ugd/229b11_cdef70ae0e7d4175a7ac53b4d9fc63f2.pdf?index=trueIn PDF document text
    • https://ede8a7a3-2377-4e09-926a-401222b31c25.filesusr.com/ugd/81c89d_5d36134f0a51412281c5adabc78ac343.pdf?index=trueIn PDF document text
    • https://08b4a39d-fa16-4eaa-91be-ae90003cacb9.filesusr.com/ugd/237bf7_fcd99677832c493db0ca755d7817b297.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/salosibejodod/free_app_messenger_lite.pdfIn PDF document text
    • https://5a1138df-423b-4a5d-a7c7-36223740754e.filesusr.com/ugd/a72fa8_a1caab0f03814782a27fcde5d20373cd.pdf?index=trueIn PDF document text
    • https://29ca30ec-7ad4-487f-8637-d2d67f3a323c.filesusr.com/ugd/10b11f_2a0588a1b7f24bb2a0885362d89331b5.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/najipavez/mesomaxufi.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_off000129be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129BE 5384 bytes
SHA-256: d7883a075bd316e10459c4fb9e43f9e5c73444f7f3b8e85e1c305923c2f029e1
font_01_sfnt_off00013c33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C33 11328 bytes
SHA-256: 45df12126d553724ffb3065fda1e539a60c2646b1a846958761f0afd71ef6dfa