Malicious PDF — malware analysis report

Static analysis result for SHA-256 21d02dc7b58bf2ae…

MALICIOUS

PDF

77.7 KB Created: 2021-03-24 03:34:13 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: bdff33dc2daaa35490dd8c721f512890 SHA-1: ed8bcb738eb4003755a6a112c6038bbf43e5346c SHA-256: 21d02dc7b58bf2ae9ef7da49f4e20613322c20f8ac7c000bc006bf0e2fe777d8
186 Risk Score

Malware Insights

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

This PDF file contains numerous external links, many pointing to disposable hosting, suggesting a link farm or phishing operation. The primary malicious URL identified is vilenefex.ru, which is likely used to host malicious content or redirect to phishing pages. The presence of a ML classifier flagging it as malicious and ClamAV detection further supports its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://vilenefex.ru/strik?utm_term=does+walgreens+have+a+blood+pressure+monitor PDF link annotation
    • http://nunobuzipame.medianewsonline.com/64572134013.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4465257/normal_5fce14be00435.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4467003/normal_600e76313ee8e.pdfIn PDF document text
    • http://nuloriwilorij.scienceontheweb.net/7_step_hurdle_technique.pdfIn PDF document text
    • http://fejukoturig.medianewsonline.com/18660299498.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4413226/normal_5fcb6389a469d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477376/normal_602f9f0a8f4be.pdfIn PDF document text
    • http://lazujifoxupa.getenjoyment.net/78463689490.pdfIn PDF document text
    • http://xesapuwax.mywebcommunity.org/42582564884.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/zagapaxa/60945712070.pdfIn PDF document text
    • https://dca540c6-954d-4243-9f09-0921753db957.filesusr.com/ugd/974a4e_9d0be0fd0f2c4d408f5333dd1c78233e.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/pibabopuduj/98229725532.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/558c92d4-9061-4843-881b-6149bc0d3e10/xumirumumetufatobewevilu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2ec3b032-ed62-47dd-a32f-0d9407c9ca81/kathie_lee_gifford_worth_2019.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0f264bce-8b62-4e04-b16c-90cc77f8a2c4/why_wont_my_husqvarna_chainsaw_start.pdfIn PDF document text
    • https://f9fc249e-2e6a-4908-9eb0-88005465a50d.filesusr.com/ugd/2530ee_d0d808dac70c4f04ab7193fe6e09578e.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/6ef63edc-c72b-4535-a646-3a259c1d6471/18586443728.pdfIn PDF document text
    • https://s3.amazonaws.com/jovekus/datuga.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e94bfd18-7c65-4f08-9e4e-e071c8674148/titelonubo.pdfIn PDF document text
    • https://s3.amazonaws.com/gudukupir/43444094262.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/32e5d2b7-fc89-4d49-8cb9-d896a1c91b59/31172648282.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6d91c083-3ebc-4264-8b6f-9867ac2d5bf2/2000_chevy_s10_ignition_wiring_diagram.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/44685bde-d9f2-4a31-86de-1fb3d7339f29/58017442315.pdfIn PDF document text
    • https://s3.amazonaws.com/mizeteb/rivizajijomamoweli.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_off0000f0f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0F7 5664 bytes
SHA-256: ca9f91ab594ae08800a71c8cbdcc4fc8243420ffd909e4d5d051de3c89921466
font_01_sfnt_off00010425.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10425 10852 bytes
SHA-256: e5e017ac536f62cc573f8823543e2048f47624af64d029862adbdfb882b0b5c7