Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b4525d7ee4fd28c…

MALICIOUS

PDF

129.2 KB Created: 2021-03-28 04:22:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 729a081f7678a75bee3a06a242013a77 SHA-1: ae50b9106376c9ae5de3cf6cca7f444667b24aaf SHA-256: 3b4525d7ee4fd28c5051aafd3b0cbf272614831ab8e5cf90677fc0abc940f6ec
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample is a PDF document that contains a large number of external links, many pointing to disposable domains or hosting services. This behavior is indicative of a link farm, often used for SEO manipulation or to distribute malicious payloads. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://nipisod.ru/strik?utm_term=the+aeneid+book+12 PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4458389/normal_602e7c7806e81.pdfIn PDF document text
    • https://xifabaruwene.weebly.com/uploads/1/3/0/9/130969291/batinapomijezetipig.pdfIn PDF document text
    • https://cdn.sqhk.co/tiwumixe/chGghie/dilarawetuzixor.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4462708/normal_5fe109f4d0d42.pdfIn PDF document text
    • https://cdn.sqhk.co/xezojutatow/jgcFsWP/43290961552.pdfIn PDF document text
    • https://cdn.sqhk.co/tabewinudeka/iehuhhD/71049968391.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4382405/normal_5feb8c261ec5d.pdfIn PDF document text
    • https://bozuwosumexoxal.weebly.com/uploads/1/3/2/6/132682772/75390da596.pdfIn PDF document text
    • https://cdn.sqhk.co/lesebonun/jeqgihb/95520823246.pdfIn PDF document text
    • https://cdn.sqhk.co/livatunozasu/Bhi6sig/foromozi.pdfIn PDF document text
    • https://kaxorude.weebly.com/uploads/1/3/4/0/134095875/8994183.pdfIn PDF document text
    • https://cdn.sqhk.co/ruzemesafe/ggc1bij/pegugegafevuduvugu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375196/normal_60241a4042ef8.pdfIn PDF document text
    • https://cdn.sqhk.co/vasozaponem/ib5jbid/new_ice_cream_flavors_at_walmart.pdfIn PDF document text
    • https://lujomawaki.weebly.com/uploads/1/3/4/5/134577487/zapip.pdfIn PDF document text
    • https://cdn.sqhk.co/tesikotuk/YUhhPhc/etrade_pro_vs_power_etrade.pdfIn PDF document text
    • https://pixerogamaba.weebly.com/uploads/1/3/1/8/131871590/2385457.pdfIn PDF document text
    • https://cdn.sqhk.co/bitomasijelo/hfncTfu/lyrics_photo_video_maker_apk.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489850/normal_602a9e637349d.pdfIn PDF document text
    • https://cdn.sqhk.co/wimiwupo/jdagdnS/wilderness_first_aid_certification_near_me.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://cef8af8d-7071-4339-ac50-fc417d371010.filesusr.com/ugd/a89196_16b36d410b2f4208bb941bfef4bf8d5c.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/vavebufevodutob/renes.pdfIn PDF document text
    • https://s3.amazonaws.com/sutawowirosuvuv/donuvajenesijojetegaganon.pdfIn PDF document text
    • https://s3.amazonaws.com/xalasawu/21868201644.pdfIn PDF document text
    • https://41fe7446-7195-45c8-906d-de5e784989f9.filesusr.com/ugd/e02969_ab264f588f73486e89787746a96da75f.pdf?index=trueIn PDF document text
    • https://46c19374-600d-43be-a5f2-d8bf07c6fddf.filesusr.com/ugd/cc94a4_fc86e68af7654c2f988d5adb075969b6.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/viromibukoleliw/sedot.pdfIn PDF document text
    • https://bed1e925-73f7-457c-87ff-53f226988024.filesusr.com/ugd/d4a8ce_e750ae46286a42aea6117f804a5770c4.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/dabatisew/40706878857.pdfIn PDF document text
    • https://2987c0f4-171e-4473-b3f1-a5468658115b.filesusr.com/ugd/75ff8a_4d16822e8a534ef095a6ef6cab1fb4db.pdf?index=trueIn 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_off0001c0e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1C0E5 4944 bytes
SHA-256: 4fc640ad1a93a3349a49ffa7bbb11f33aafc0f846538d3ada56c483a25a5d75d
font_01_sfnt_off0001d1b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1D1B8 10944 bytes
SHA-256: 799cefdec2b441e9b6a4d18e87d8516a33d7a36a1aa616c6b4c140de62699687