Malicious PDF — malware analysis report

Static analysis result for SHA-256 919ca558462490e7…

MALICIOUS

PDF

76.9 KB Created: 2021-03-14 14:18:39 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 835358dc93b70484795b6512964cf3dc SHA-1: 283480d8ae5f19ed673e0448704e91f1f7c59f48 SHA-256: 919ca558462490e71dd1f4afd9c91cba1d41329a207cb8c95a1b5ca5022d5e48
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by multiple heuristics and an ML classifier, with ClamAV detecting it as a phishing trojan. It functions as a link farm, containing numerous external URLs pointing to other PDF documents, many hosted on disposable domains. The primary purpose appears to be SEO manipulation or distributing further malicious content, as indicated by the 'PDF_SEO_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristics.

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://kuzutuzo.ru/strik?utm_term=how+to+change+oil+in+2013+lexus+rx+350 PDF link annotation
    • https://mepapezivodeno.weebly.com/uploads/1/3/0/9/130969154/zegaxajozazoweg-vepaletugubi-kotatazirubaku-zekoxanopibali.pdfIn PDF document text
    • https://cdn.sqhk.co/rajosibakulu/gghbhho/pandemic_isolation_game.pdfIn PDF document text
    • http://widusal.22web.org/xobupa.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4404503/normal_5ff8032197523.pdfIn PDF document text
    • https://cdn.sqhk.co/tuxonewebuke/7eiiB8Z/nukonavopasit.pdfIn PDF document text
    • https://muwirejevom.weebly.com/uploads/1/3/1/8/131857435/5933657.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4472760/normal_6003bdd132617.pdfIn PDF document text
    • https://cdn.sqhk.co/jukunobegabe/hejjgdv/yeezy_boost_350_v2_black.pdfIn PDF document text
    • https://manapefowuv.weebly.com/uploads/1/3/4/6/134605974/jabigosesufipa.pdfIn PDF document text
    • https://noduxexoretan.weebly.com/uploads/1/3/5/9/135993764/56a65b8545e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387052/normal_601865054c8ce.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://japesexazi.rf.gd/what_do_self-defeating_mean.pdfIn PDF document text
    • http://podekorutad.rf.gd/land_purchase_and_sale_agreement_template.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4c7b2f38-30cf-4d38-8a77-adef269f2b5c/oracle_sql_string_concatenation_in_where_clause.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/abf2fa4b-df34-4c7e-a042-1615ff7dc61a/honda_eu2200i_for_sale_home_depot.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/df33587e-257f-4f53-84b6-9372a7ff7bbd/27114227267.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d66dbed5-23bc-4c9f-a7cf-e968ff094348/buzz_lightyear_lego_instruction_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2444595b-38b4-43d7-836f-a0330de137cf/xefukuzomexalavurivob.pdfIn PDF document text
    • http://werexixudi.rf.gd/wordscapes_answers_level_400.pdfIn PDF document text
    • http://gikisomu.epizy.com/harry_potter_und_die_kammer_des_schreckens_full_movie_german.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/144664a7-71be-4322-847e-22737837a85b/41043523820.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eb5c1878-5048-4b13-afab-f3797b84ba31/44372672409.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_off0000ee86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE86 5796 bytes
SHA-256: e8dfcb55ab08829a96fa82e5c29d12026bcdb1305ae299e39595eab7ce5abca0
font_01_sfnt_off00010259.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10259 10476 bytes
SHA-256: 2c2e9174b712e91764032a04133e0420044b73fa9ce08c440fe8dc9ca00540ee