Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4151f84c8e4c2ff…

MALICIOUS

PDF

86.5 KB Created: 2021-03-14 15:23:40 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: d3fc45f007965b48b846becbe6201482 SHA-1: 7f58804a43fe0c352322636a6745154930443d9b SHA-256: e4151f84c8e4c2ff6ae4169879544b3b67ea037df9f10953778cf0980aa0a18b
186 Risk Score

Malware Insights

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

The sample was identified as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous external URLs pointing to other PDF documents, many hosted on disposable domains. The primary malicious URL observed is https://dugedepap.ru/strik?utm_term=horton+hears+a+who+full+movie+free+online, which likely serves as a redirector or landing page. The PDF structure and embedded links suggest an attempt to manipulate search engine results or distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://dugedepap.ru/strik?utm_term=horton+hears+a+who+full+movie+free+online PDF link annotation
    • https://dinurafilaxu.weebly.com/uploads/1/3/4/6/134621410/77e26c.pdfIn PDF document text
    • https://cdn.sqhk.co/bepeguvovori/fifrgcR/susigesovoxoxiwaroti.pdfIn PDF document text
    • https://cdn.sqhk.co/wifavizen/giVHCgh/smart_civil_id_kuwait.pdfIn PDF document text
    • https://cdn.sqhk.co/bavisimupux/ihjZA84/11123156482.pdfIn PDF document text
    • https://cdn.sqhk.co/lesasafo/ghhbghY/sotod.pdfIn PDF document text
    • https://cdn.sqhk.co/mepapogivoma/wjdECjf/electrical_code_conduit_fill.pdfIn PDF document text
    • https://cdn.sqhk.co/lojosewude/ieUifWz/19381202713.pdfIn PDF document text
    • https://maladebo.weebly.com/uploads/1/3/4/3/134305387/3790532.pdfIn PDF document text
    • https://cdn.sqhk.co/jixuvepabu/nD1ji7j/vakurenuvukamutaw.pdfIn PDF document text
    • https://xapunuzut.weebly.com/uploads/1/3/4/6/134683745/rijarilapunemolabofu.pdfIn PDF document text
    • https://jinobodusere.weebly.com/uploads/1/3/4/7/134722577/zasagonerug_julavewezewex_kubujubitoget.pdfIn PDF document text
    • https://sejexogubason.weebly.com/uploads/1/3/1/0/131070030/45a505cc98f3.pdfIn PDF document text
    • https://litepuvib.weebly.com/uploads/1/3/4/7/134741427/588cef3.pdfIn PDF document text
    • https://cdn.sqhk.co/tokafumotebi/GhhplhF/17097329158.pdfIn PDF document text
    • https://babixugopanodip.weebly.com/uploads/1/3/5/3/135382952/9999690.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/ad03c023-ff0e-48a4-8df3-6b803abdbabc/41414528281.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/898e660f-04a7-4ef1-b6bc-33418139b70f/kafepowo.pdfIn PDF document text
    • https://b3a1a1c9-4f8f-4fb8-b7cc-7339030cc889.filesusr.com/ugd/162fe6_b27064c1a88e4db3bfc13c4909fc9164.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/82eaeb24-56a5-4ec6-adee-551e158b092b/war_horse_play_cast_list.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a728a454-def4-4bd0-862d-d36979822fce/ice_breakers_holiday_mints.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fe30341c-0d5b-42e8-bb98-8e2dd40366c1/vidiwowowapefi.pdfIn PDF document text
    • https://493f174a-a540-412c-bacb-e5b7b26cbfcf.filesusr.com/ugd/95bb70_86a636976ffe44d49e5b0597c3af8726.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_off00011615.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11615 5120 bytes
SHA-256: 072a2da662055dfde2ee4e4d6db01e8a0c693541ae18bfe53e41766d38a3429b
font_01_sfnt_off0001276c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1276C 10772 bytes
SHA-256: ad774f9ca36347081bca8095374e1b0b6707e3321ae9237f04aa320aa4b405ae