Malicious PDF — malware analysis report

Static analysis result for SHA-256 6ff4c045238208e8…

MALICIOUS

PDF

74.1 KB Created: 2021-03-16 10:49:51 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 44c08e884b2f96e7784f825e21f2275a SHA-1: 5bcc8d2bd2ee0a35ed0dbb68c34e583112723f75 SHA-256: 6ff4c045238208e83bc9cf2d018670222ea69e29522a258b195ba2ad1260625b
244 Risk Score

Malware Insights

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

The PDF document was flagged by multiple heuristics as malicious, including a redirector link and a large link farm on disposable hosting. The embedded URLs suggest an attempt to direct users to potentially harmful external sites, likely for SEO spam or phishing. While no scripts were explicitly extracted, the nature of the embedded links and the ML classifier output strongly indicate malicious intent.

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://crophysi.ru/123?utm_term=character+count+google+sheets In PDF document text
    • http://pakirekugep.scienceontheweb.net/winbook_tw700_tablet_manual.pdfIn PDF document text
    • https://xosipepimebat.weebly.com/uploads/1/3/2/6/132682768/182b3ec7733abde.pdfIn PDF document text
    • https://cdn.sqhk.co/gijimexuv/ij8IOia/15882048235.pdfIn PDF document text
    • http://jaralet.getenjoyment.net/will_cvs_check_my_blood_pressure.pdfIn PDF document text
    • https://cdn.sqhk.co/rivinodati/haL2hjA/design_blogger_template_from_scratch.pdfIn PDF document text
    • https://cdn.sqhk.co/soxosovave/uheidqY/reverse_dipper_x_pacifica_comic.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367289/normal_5fe995813649b.pdfIn PDF document text
    • https://logutidukikov.weebly.com/uploads/1/3/1/3/131380383/javuvuvir.pdfIn PDF document text
    • http://ruvujagefeko.mygamesonline.org/fusawuvobizit.pdfIn PDF document text
    • http://nigavereke.mygamesonline.org/adding_and_subtracting_fractions_with_like_and_unlike_denominators_worksheets.pdfIn PDF document text
    • https://cdn.sqhk.co/jotepomi/ahipghy/promotional_stress_balls_uk.pdfIn PDF document text
    • https://vunidiripoga.weebly.com/uploads/1/3/1/4/131453449/lojezuwepujeg.pdfIn PDF document text
    • https://viduxetejogat.weebly.com/uploads/1/3/4/6/134600114/8457225.pdfIn PDF document text
    • https://cdn.sqhk.co/pirujezexod/e1ijgfg/11895218303.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4407724/normal_60318583a6eeb.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://jomopizemiz.onlinewebshop.net/zerodha_varsity_module_4.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/84e2ddc2-ed9b-4359-acf9-c09d18e5b593/xinijujex.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7e6724ec-bec0-4292-ae2a-9acdb82cf7e7/waxugorobejoso.pdfIn PDF document text
    • http://joberemig.atwebpages.com/kangen_water_benefits.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_off0000e607.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE607 4968 bytes
SHA-256: a0909469a989f89b620f3c28c811656e7fb79e49f4f302abaf24ddef0c01491f
font_01_sfnt_off0000f6de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6DE 10640 bytes
SHA-256: 5585528e4fc0396d587863205d04af4dc1ada0b3ed6bec5427058752dba1d944