Malicious PDF — malware analysis report

Static analysis result for SHA-256 900116f1a9cad929…

MALICIOUS

PDF

74.8 KB Created: 2021-03-20 17:54:08 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: 5a906528bacb37d0a5caf9162457fa7e SHA-1: 1c5d27aa59d95b1695f224561e6aaa0a8aeef187 SHA-256: 900116f1a9cad9294344bdeedf9e12cc761bd671a227a4b775359ce93589a82a
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to disposable hosting services, indicating it is part of a link farm or SEO manipulation scheme. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of techniques used to redirect users to malicious sites.

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://pelibifir.ru/strik?utm_term=dynamic+equilibrium+human+anatomy+definition PDF link annotation
    • https://cdn.sqhk.co/sugutomipu/NHZibuS/kannada_bhavageethe_deepavu_ninnade_song.pdfIn PDF document text
    • https://napujokid.weebly.com/uploads/1/3/5/3/135339673/2129626.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489045/normal_604edfee1964c.pdfIn PDF document text
    • https://sudomudes.weebly.com/uploads/1/3/0/8/130874284/321315.pdfIn PDF document text
    • https://zodixezujiz.weebly.com/uploads/1/3/5/3/135345824/0ef892b1cc.pdfIn PDF document text
    • https://vemegerefawobe.weebly.com/uploads/1/3/2/6/132682093/runapada.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402280/normal_6035ad172fc76.pdfIn PDF document text
    • http://zuzatew.medianewsonline.com/40898739549.pdfIn PDF document text
    • https://cdn.sqhk.co/tokebamojos/aYhbmUP/rafazutolubufelasoxu.pdfIn PDF document text
    • https://xavapijiwo.weebly.com/uploads/1/3/3/9/133997403/36dfc7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388421/normal_5fd8d5258a37a.pdfIn PDF document text
    • http://zuregazezoral.mygamesonline.org/a_moveable_feast_hemingway.pdfIn PDF document text
    • https://cdn.sqhk.co/gituridewo/Y7qu2cG/nadopurimat.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476767/normal_601ae480a932b.pdfIn PDF document text
    • http://fikakutipid.mygamesonline.org/psc_bulletin_diamond_jubilee_edition.pdfIn PDF document text
    • https://cdn.sqhk.co/sopirisaset/jeaSrkg/gavekaj.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://vokesakogo.onlinewebshop.net/solo_arenoso_e_argiloso.pdfIn PDF document text
    • https://0dea665b-aaaa-42f3-a52c-f86f0fd1efa2.filesusr.com/ugd/8b9728_a7cbd71f1b6f452a85b669c293b7d115.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/wonumafubij/ios_13_developer_beta_profile_ota.pdfIn PDF document text
    • https://3ea853e4-7f2b-4fb0-9229-b04907a1e321.filesusr.com/ugd/d94095_c8bba8971eca49b8a80c8434a351f0ed.pdf?index=trueIn PDF document text
    • https://b1706aec-e9b1-4c6c-9a93-f14ef4a1c402.filesusr.com/ugd/3b47cb_fb45a5c28cac413c88f4f84cf2e7d313.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/davawina/steely_dan_peg_sheet_music.pdfIn PDF document text
    • https://s3.amazonaws.com/mivokozibu/carpentry_for_dummies_free_download.pdfIn PDF document text
    • http://maretubozewugi.myartsonline.com/linear_synchronous_motor.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_off0000e778.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE778 5448 bytes
SHA-256: 840bad0126c9c172ad1cd97a267c57d60703032e6cae60b123ef2a1f5039fa10
font_01_sfnt_off0000f9df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9DF 10432 bytes
SHA-256: 89181574116ac58dffb914d65b28f5e6b22d6d4cb7d19a5410a63017b3d50cfc