Malicious PDF — malware analysis report

Static analysis result for SHA-256 61c32804543a7077…

MALICIOUS

PDF

115.7 KB Created: 2021-05-12 11:19:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 503c0d1c4f3fe346b55c48468db195b4 SHA-1: 309a5344f0840a711e70ca6d434b7a75426dcb00 SHA-256: 61c32804543a7077bd33cb8c3af34652aabe9a9b34b4fed9d8588de1968a0147
186 Risk Score

Malware Insights

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

This PDF file contains a large number of external links, many pointing to disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and numerous external URIs are indicative of a phishing or malware distribution campaign, likely initiated via spearphishing.

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://nipisod.ru/strik?utm_term=cuadernillo+de+ingles+basico+pdf+para+adultos PDF link annotation
    • https://cdn.sqhk.co/dezosanag/GfgchaA/dictionary_app_free_download_english_to_bengali.pdfIn PDF document text
    • https://forelidik.weebly.com/uploads/1/3/0/7/130775511/4bc2d026eb.pdfIn PDF document text
    • https://katibaluzopoxu.weebly.com/uploads/1/3/0/7/130738884/bokofodeloji.pdfIn PDF document text
    • https://simogewijak.weebly.com/uploads/1/3/4/6/134642120/jaxareguzupij.pdfIn PDF document text
    • https://xitititoludazo.weebly.com/uploads/1/3/5/9/135987602/fafalukom-rimeja.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445324/normal_60467784a12ef.pdfIn PDF document text
    • https://cdn.sqhk.co/poxudanefisi/aifibje/random_thai_alphabet_for_design_fonts.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4409610/normal_6002495638f45.pdfIn PDF document text
    • https://wefapewirevuvik.weebly.com/uploads/1/3/4/6/134667644/luwiviliw-fugoso-wopexir.pdfIn PDF document text
    • https://fozixaxo.weebly.com/uploads/1/3/4/6/134665632/kapuririjazeti-putapanepuze-juwedisiwuv.pdfIn PDF document text
    • https://cdn.sqhk.co/nupasoxure/h0jahi9/79848507586.pdfIn PDF document text
    • https://cdn.sqhk.co/guranotup/TChecjj/nostalgia_cotton_candy_machine_walmart.pdfIn PDF document text
    • https://cdn.sqhk.co/buwoxatixun/4gfRUhg/2956827980.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/bubeto/what_does_killing_zombies_in_a_dream_mean.pdfIn PDF document text
    • https://s3.amazonaws.com/kezemiradigu/44044210437.pdfIn PDF document text
    • https://51f47fa2-20f7-4ec4-bb91-8ae4aee689b4.filesusr.com/ugd/917232_7c7726d569d84737b2613d0b1a9bbd35.pdf?index=trueIn PDF document text
    • https://b27aca93-056c-4dd2-83a6-fd909c9f709d.filesusr.com/ugd/2ba3ac_d4c6c6e352a6455d886d13a944e1406b.pdf?index=trueIn PDF document text
    • https://04a9e765-cf69-4035-9b9a-998d8fb4e692.filesusr.com/ugd/8c5016_9daade4326b641e39daed1b578d0a552.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/mexavofezoxi/ardamax_keylogger_for_android_mobile.pdfIn PDF document text
    • https://93dbb2ad-f1e8-4c6c-adfd-2ef134399473.filesusr.com/ugd/df4650_e5bfae0011474774a5536d40950c7316.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000170ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x170AB 4580 bytes
SHA-256: d72b62eafcd3094bdc631fe8ba329cc9ccabf4c0d1b98bd971ac2b4bc30ea712
font_01_sfnt_off000180db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x180DB 5368 bytes
SHA-256: 7bd24b574b3b558fba9a00e99cd0018cb988cfb5f61d849c1070fb3d72be9083
font_02_sfnt_off0001931f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1931F 14088 bytes
SHA-256: 679480dac4f753a5bb3b3be414fa999d13fe79f44e4fa536f6269beac503cb1f