Malicious PDF — malware analysis report

Static analysis result for SHA-256 31a052e552fa0227…

MALICIOUS

PDF

79.9 KB Created: 2021-05-12 06:18:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: f12704b24abcccfc2c44d912ccc423d5 SHA-1: 213351394dadbf8d0aeb8c3ecbd6feeca826f0e9 SHA-256: 31a052e552fa0227f27709d412edd1f6d135b95892529d9ab123c080dc6178d2
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many of which are hosted on disposable domains and appear to be part of a link farm. The embedded content suggests a lure related to a search query, indicating a phishing or SEO manipulation tactic. ClamAV and ML classifiers also flagged this PDF as malicious, specifically as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9967

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://leonvi.ru/strik?utm_term=what+is+salt+chemical+formula PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4463554/normal_6051ef1e6ffea.pdfIn PDF document text
    • https://cdn.sqhk.co/muwazubivotu/ghQwjhx/3d_origami_dragon_dinosaur_tutorial.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4484154/normal_5ff974896af0b.pdfIn PDF document text
    • https://cdn.sqhk.co/sileluzorupo/Vgdhdhe/best_adventure_romance_books_for_adults.pdfIn PDF document text
    • https://bajekilirevi.weebly.com/uploads/1/3/4/8/134868337/4198878.pdfIn PDF document text
    • https://nozonefabizeg.weebly.com/uploads/1/3/0/9/130969368/fivubuxagifad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370744/normal_606471709025b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4404296/normal_5ff073a201f47.pdfIn PDF document text
    • https://cdn.sqhk.co/fosulavale/bSjjhh2/9652822765.pdfIn PDF document text
    • https://jedopebo.weebly.com/uploads/1/3/4/8/134889916/3e4ee0b8770.pdfIn PDF document text
    • https://cdn.sqhk.co/lisakopew/Xbvihhc/need_for_speed_no_limits_vr_android.pdfIn PDF document text
    • https://labadejasif.weebly.com/uploads/1/3/4/7/134718281/mizabetitijejepo.pdfIn PDF document text
    • https://zagumugapepari.weebly.com/uploads/1/3/1/6/131636872/3513086.pdfIn PDF document text
    • https://jowidirususonin.weebly.com/uploads/1/3/0/7/130775515/zokubuzuxok.pdfIn PDF document text
    • https://rupubonu.weebly.com/uploads/1/3/0/7/130739332/3943090.pdfIn PDF document text
    • https://cdn.sqhk.co/fimegasaz/hPOoWhg/78949172836.pdfIn PDF document text
    • https://gopogaxewose.weebly.com/uploads/1/3/4/0/134013169/6fb249709f8.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4470222/normal_6007a8a0352c4.pdfIn PDF document text
    • https://pigukoziluluz.weebly.com/uploads/1/3/4/8/134896600/afb6c5d3d1.pdfIn PDF document text
    • https://jidedenevunuva.weebly.com/uploads/1/3/4/4/134498736/tizezujudipuriz.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/dikomavomem/58720065622.pdfIn PDF document text
    • https://ca108e69-7b6b-43f0-8f16-d96ebeb8a33d.filesusr.com/ugd/79e0dc_91e494f4de994975b31e36550debf3ce.pdf?index=trueIn PDF document text
    • https://aa3bb5c3-2bd4-4791-9e2a-6e31d5009b04.filesusr.com/ugd/60e703_99d7f5282e4b4e05afe3215679ee14c6.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/fujadabez/recommendation_letter_sample.pdfIn PDF document text
    • https://5057b38b-f250-4925-a5fd-2dbc054a2c1f.filesusr.com/ugd/25ee37_cad2d4d68317423b830c4125d2c22b44.pdf?index=trueIn PDF document text
    • https://cdfb6f36-dde2-4af5-b3b7-55ff39976061.filesusr.com/ugd/c6ac46_dbb45b0773b644f787a3334c14612d21.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_off0000fad7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAD7 5136 bytes
SHA-256: 6baba98c7729863f77d2acdeb587033b0751b209bdde365975943da723950482
font_01_sfnt_off00010c2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C2D 11148 bytes
SHA-256: 882db6e33a6a77ae90cc6a9fa752651b3c1f08b99a9083fcbedaa43fc4e6166d