Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3737690a4eba4d4…

MALICIOUS

PDF

73.4 KB Created: 2021-06-12 11:27:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 5d3a4867096e258f74c9dae069118fa4 SHA-1: 0c9ab3004cf299d87e56eacba59bd322265205ec SHA-256: a3737690a4eba4d411ece193ccdc071ac553dc0623176724e0bb4433bf936c6e
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • 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.
  • 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://coretry.ru/uplcv?utm_term=siddharameshwar+maharaj+books+pdf PDF link annotation
    • http://architects-desk.com/uploadsfile/kusikepigawibokadebixamev.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/cf7be1a1ab2893bb80b9f763c1514fbd/65562813371.pdfIn PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/ppl0n1k3utuc524pb95vjriqp0/guvovofuzazefakugar.pdfIn PDF document text
    • https://dineflon.com//files/xuder.pdfIn PDF document text
    • http://vdadanang.vn/app/webroot/assets/files/18615740754.pdfIn PDF document text
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7a31c6516---69408737263.pdfIn PDF document text
    • http://apartamentosalbatros.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091034e6b939---19622015300.pdfIn PDF document text
    • http://meble-tk.pl/userfiles/file/kozajojokojubu.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/503ea3b1a5eef2c5cdf53a16df9f2a1c/lanisufedibixologujawuf.pdfIn PDF document text
    • http://kibbkw.com/uploads/file/lutufefidezukusonibiz.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/0bd1b08f3509d0feda391ac3b8930119/gojefarewiweboji.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1608a14c7595ba---33243409485.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f0021a77ec---66462724955.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1607bdfb784e8b---sedabel.pdfIn PDF document text
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/698e13b84ab09944da46b1b268d609b3/fudolafavanobeve.pdfIn PDF document text
    • http://bhk-aindling.com/userfiles/files/felaza.pdfIn PDF document text
    • http://musiconthebay.org/clients/2/26/269dd5bc96e197da989a8dccc71442af/File/zesilujobo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e2ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2EC 5724 bytes
SHA-256: 38f175443cf3fb0e24427ee399a90784232fe1dd2e849e19faf9aa8fc5545e54
font_01_sfnt_off0000f645.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF645 11184 bytes
SHA-256: d2cbc18d02813329a71be000f39817c6dc0658f04b8c17f3da06f7aa75bb8a48