Malicious PDF — malware analysis report

Static analysis result for SHA-256 759ad62147665c26…

MALICIOUS

PDF

183.0 KB Created: 2021-03-04 08:10:54 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: 4212a2a76a69d5530c9bbc9e7df43fa6 SHA-1: 0e7e8df976100b8123b2f0f2d52ee5098fe1d060 SHA-256: 759ad62147665c269d66df0d5be76edf2da345680c4159c8b8d95593ef58a26e
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF file was detected as malicious by ML classifiers and ClamAV, specifically identified as a phishing lure impersonating LinkedIn. The embedded URL, https://nipisod.ru/wb?keyword=andromeda%20strain%202008%20full%20online, is hosted on a domain that does not match the impersonated brand, indicating a credential harvesting attempt. The document's structure and numerous external links suggest it functions as a link farm designed to redirect users to malicious sites, likely exploiting PDF vulnerabilities to achieve execution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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
  • Brand-impersonation credential phishing lure high SE_BRAND_CREDENTIAL_PHISH
    Document impersonates a well-known consumer brand and uses account-security / verification language ('unusual activity', 'account on hold', 'verify your account') to steer the reader to a credential-harvesting link. Corroborated by: call-to-action link host does not match the impersonated brand: https://nipisod.ru/wb?keyword=andromeda%20strain%202008%20full%20online.
  • 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/wb?keyword=andromeda%20strain%202008%20full%20online PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4386848/normal_603893681987d.pdfIn PDF document text
    • https://cdn.sqhk.co/tumowara/ehfRibR/warframe_limbo_theorem_no_blueprint.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426262/normal_5fd62ab072a8d.pdfIn PDF document text
    • https://cdn.sqhk.co/vitimosugu/fjdpVpT/daxozobumuresukanojujavek.pdfIn PDF document text
    • https://cdn.sqhk.co/fakupavod/jjCgjD0/89186715928.pdfIn PDF document text
    • https://cdn.sqhk.co/vipujitebiki/aDhdvJp/head_boxing_d_d_dream_mod_apk.pdfIn PDF document text
    • http://manuximaxemeje.scienceontheweb.net/tegugozakega.pdfIn PDF document text
    • https://cdn.sqhk.co/buwaxaxodi/iVFFDB6/peligoxipezagisefowewotef.pdfIn PDF document text
    • https://cdn.sqhk.co/mawejoxejobe/ijgiahd/change_messenger_notification_sound_iphone_xr.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4425504/normal_5feb85f08cc6c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4487007/normal_602b07fb93d9f.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://faxanudof.epizy.com/saucony_guide_iso_size_10.pdfIn PDF document text
    • https://s3.amazonaws.com/nilititonawafim/fire_prevention_and_safety_crossword_puzzle_answers.pdfIn PDF document text
    • http://bukaduxanob.epizy.com/lease_agreement_template_south_africa_doc.pdfIn PDF document text
    • http://mojofukiw.epizy.com/dslrbooth_crack_free.pdfIn PDF document text
    • https://s3.amazonaws.com/dozore/66253877366.pdfIn PDF document text
    • http://gozosowizopuk.rf.gd/hp_laserjet_pro_400_color_m451nw.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0002707f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2707F 5512 bytes
SHA-256: 1db4515375c77a7cb3c0b7c463b42168c68c9ba064eab9ef28e868294445ae5f
font_01_sfnt_off0002831b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2831B 17348 bytes
SHA-256: df44c5aa3d91a7c90a764e51507d3e5b25263f77c3aa849a921915eb679eec7f
font_02_sfnt_off0002b8ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2B8ED 16036 bytes
SHA-256: 35d3440dae1ebc896564e4e6f70ea95aa3a30a1ac603c7fffbb21b68b8b72e2f