Malicious PDF — malware analysis report

Static analysis result for SHA-256 371d170dcdfd400a…

MALICIOUS

PDF

78.4 KB Created: 2021-04-21 00:05:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 44e2dbbfab4e15d5e7bd7792b2a7145b SHA-1: 7cc6268339684c2cc2ee8ad98de69dfe83b53dad SHA-256: 371d170dcdfd400a65afe0ce182169f03de71e747379131ef050ecd5e9a04059
186 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, suggesting it functions as a link farm, potentially for SEO manipulation or to direct users to malicious content. The presence of embedded URLs and the PDF_SEO_LINK_FARM heuristic further support this attack pattern. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://druttle.ru/strik?utm_term=how+to+report+employee+stock+options+on+tax+return PDF link annotation
    • https://cdn.sqhk.co/kowukogifaw/66hdoOX/bewars_movie_ringtones_naa_songs.pdfIn PDF document text
    • https://cdn.sqhk.co/papusabefo/ekwjCig/launcher_apk_2020.pdfIn PDF document text
    • https://cdn.sqhk.co/fefuxumito/gcimZhi/dowenawupibudenasam.pdfIn PDF document text
    • https://fopunideneluw.weebly.com/uploads/1/3/5/9/135965314/16a8ed64.pdfIn PDF document text
    • https://cdn.sqhk.co/valujoper/61ejije/train_go_railway_simulator_download.pdfIn PDF document text
    • http://rapugazif.22web.org/lalevevakafixitefokegifa.pdfIn PDF document text
    • https://cdn.sqhk.co/lojadisexudo/pf9ygiT/w3schools_html_table_header.pdfIn PDF document text
    • https://dibalinelig.weebly.com/uploads/1/3/1/3/131380687/banuwasabo-posot-muropodetomane-fumajif.pdfIn PDF document text
    • https://powotatetodo.weebly.com/uploads/1/3/0/7/130738650/wojow-levituweje-nugarab.pdfIn PDF document text
    • http://vabakavolageni.22web.org/2743472275.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://ad0d0dbb-669b-46a9-85df-79487014a0f3.filesusr.com/ugd/00d95d_3e25bfc92c34426fb4110478048cbe02.pdf?index=trueIn PDF document text
    • https://26f2e344-8444-46ea-90c9-5a893bcc2fb3.filesusr.com/ugd/b8c837_065548dda89a4b49aa5286968f656114.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/tosevud/empty_pathfinder_character_sheet.pdfIn PDF document text
    • https://e222b685-7c7f-4cee-b050-218328c89257.filesusr.com/ugd/c0232f_dc512e916df04f1dad847aa2c2ac305b.pdf?index=trueIn PDF document text
    • http://safasufozoz.rf.gd/hink_pinks_level_c_hard_answers.pdfIn PDF document text
    • https://0ecef3a8-5193-4df1-8dcb-1b7dd0f2be2a.filesusr.com/ugd/e6092c_4b9a0882dca44bbb960f8c3e00aa6a2b.pdf?index=trueIn PDF document text
    • https://03df74f7-894d-4c84-999e-da2b33eb06f5.filesusr.com/ugd/4c7733_05c600ad3b2d4957bee3837c5d40257d.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/boxujetanonikuv/24847827606.pdfIn PDF document text
    • https://s3.amazonaws.com/tiluwisulepam/adblock_block_ads_apk.pdfIn PDF document text
    • https://s3.amazonaws.com/xamapebonijos/pivoroje.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_off0000f447.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF447 5364 bytes
SHA-256: 77055f760a0e4c5dea829b905b40f8c8718a78a32a19828d08c85a7648d147d1
font_01_sfnt_off0001068b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1068B 10916 bytes
SHA-256: 146b59acdc40f31558ab732dc87574ae51e447fdb0f54bd52b6fed73f5b987c1