Malicious PDF — malware analysis report

Static analysis result for SHA-256 420da412d81e79ac…

MALICIOUS

PDF

81.5 KB Created: 2021-09-05 12:53:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: b7303cef1740d59419d7c1fc7c34aac2 SHA-1: 5facd78f512eae3001246ec585bfaec0ec7bb15d SHA-256: 420da412d81e79ac35c704e913bccbe292425333729997072d81946cc45818fd
164 Risk Score

Malware Insights

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

The PDF contains an embedded JavaScript stream and a significant number of external links, many pointing to other PDF files hosted on compromised or disposable domains. This indicates the document is likely part of a phishing or spam campaign designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://ketchas.ru/uplcv?utm_term=aestivation+in+animals+pdf PDF link annotation
    • http://sgadsahodayatarntaran.org/sahodyatarntarannew/userfiles/file/82215744907.pdfIn PDF document text
    • http://restorationteleconference.com/clients/73716/File/nakavikafeg.pdfIn PDF document text
    • http://euroteam.vn/ckfinder/userfiles//files/53900483448.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c792e47cdf6---24857575598.pdfIn PDF document text
    • https://mackbeks.com/files/file/74252542224.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/5827870721.pdfIn PDF document text
    • http://agt.es/files/galeria2/files/98808902517.pdfIn PDF document text
    • http://cuanhuaabshanquoc.vn/files/ribuburenikoxemaz.pdfIn PDF document text
    • http://zhuoer.ltd/userfiles/file/jalivovizawazurutexo.pdfIn PDF document text
    • https://zenit-npk.ru/files/file/xalupufok.pdfIn PDF document text
    • http://highlandlynxotic.com/clients/7/73/73cf6ae24f8ea70eb1cbac1dff6b0f9e/File/77135708640.pdfIn PDF document text
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/vhmu4knredgiejfhg5h569fa8i/rufubedenali.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f0bded0a1b2---776550192.pdfIn PDF document text
    • https://alakharia.com/public_html/userfiles/file/71175161892.pdfIn PDF document text
    • http://rayer.cn/d/files/josorebediwemubutivejedam.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e95f873f240---xotinuroxubaz.pdfIn PDF document text
    • http://poetische-malerei.de/web/editor/files/buxinurosokivomubedivon.pdfIn PDF document text
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/k1godfnd43s1bispd31bpj5qd4/gajogemux.pdfIn PDF document text
    • https://primer-spb.ru/files/files/19949154634.pdfIn PDF document text
    • https://bankkartya.hu/js/ckfinder/userfiles/files/begefiboropexoroduwaman.pdfIn PDF document text
    • http://modellszerviz.hu/userfiles/file/92522800264.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/0m3asrip6087fj60j6reooarj3/xaxanirula.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dd52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD52 16656 bytes
SHA-256: 6d705504aa79a28d370602b0fe5ec9a25fc21e07efef77454afd6625d3252755
font_01_sfnt_off00010837.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10837 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001204e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1204E 10608 bytes
SHA-256: 35e71b71e9b22c6269ede5f1ffe2ab38dd3d4a24805f546d3f6bd566e7ca8f8d