Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb436aa00430d525…

MALICIOUS

PDF

116.4 KB Created: 2021-03-17 02:52:38 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: ea5e9af25ebe903651a277bb7c11b3b1 SHA-1: 7892d73e6b1821e88ea337f7222dd53145862b4d SHA-256: cb436aa00430d525db9d94054a15f5856012f372891afc167b07c4d192941da5
186 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as a link farm, containing numerous external URLs pointing to various domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure itself facilitates the redirection to these external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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/123?utm_term=corona+renderer+1.+7 PDF link annotation
    • https://cdn.sqhk.co/jopubelo/9hihbjh/supreme_duelist_stickman_mod_apk_2020.pdfIn PDF document text
    • https://cdn.sqhk.co/wadupaxi/cegiLif/hidden_valley_orchards.pdfIn PDF document text
    • https://jotitotibewava.weebly.com/uploads/1/3/1/3/131383271/4cb08.pdfIn PDF document text
    • https://cdn.sqhk.co/zatovafer/Njidcgg/luff_s_go_jungle_adventure_park.pdfIn PDF document text
    • https://vedexojofidas.weebly.com/uploads/1/3/4/5/134581268/85e5e2aaf25.pdfIn PDF document text
    • https://zekedijudanafow.weebly.com/uploads/1/3/0/8/130874467/3242418.pdfIn PDF document text
    • https://cdn.sqhk.co/dawafawux/he1heRs/ziwuz.pdfIn PDF document text
    • https://cdn.sqhk.co/mepapogivoma/hicgcgd/sinozej.pdfIn PDF document text
    • https://cdn.sqhk.co/woxemumi/jjtifid/guvipugexa.pdfIn PDF document text
    • https://gataveboturifon.weebly.com/uploads/1/3/1/1/131164486/jozixazebajife.pdfIn PDF document text
    • https://cdn.sqhk.co/kupuruvew/ePysjig/kof_98_um_ol_best_characters_2020.pdfIn PDF document text
    • https://gawujura.weebly.com/uploads/1/3/5/3/135325150/xawetovowozi-kovomipuvakoti-tulamu.pdfIn PDF document text
    • https://voxonororipesap.weebly.com/uploads/1/3/5/3/135383222/xedasobodalewa-subanovuviz.pdfIn PDF document text
    • https://muxojuwarerufi.weebly.com/uploads/1/3/5/3/135388895/sizulofitenufe.pdfIn PDF document text
    • https://zifupowipowiku.weebly.com/uploads/1/3/4/7/134722678/wufuke.pdfIn PDF document text
    • https://felonuwonab.weebly.com/uploads/1/3/0/8/130814100/solof.pdfIn PDF document text
    • https://fisolaxarod.weebly.com/uploads/1/3/4/4/134471724/5a7d6.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/5cbe37fa-55ab-4fbc-a084-a0fb8cd90a70/fender_blues_deluxe_reissue_for_sale_uk.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0a6d1147-d501-4a07-8a4c-1e6a5b958ea4/troy_bilt_horse_tiller_pto_attachments.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7924a54b-6d79-4617-bc8d-b4d20148d851/68219181746.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a6e271f4-edfd-4940-bcd3-884018cc56e3/wukolus.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b30404cb-457e-41c2-8715-2d5139b6d08c/can_you_recycle_books_in_blue_bin.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001277f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1277F 32320 bytes
SHA-256: e84509fd68f952d596ffe4ecc66da3378dda637104ce4134acc3d21b684d6884
font_01_sfnt_off00018b0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18B0A 4676 bytes
SHA-256: 554630097481e36cbb3295e67902026b35fcbe4e2885dad22743484378ebc687
font_02_sfnt_off00019b0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19B0A 11364 bytes
SHA-256: f633a88dedf8881acc08cb58b095c8d18d11090634b799ff38871584ca04a710