Malicious PDF — malware analysis report

Static analysis result for SHA-256 3bcd88d9e520f09b…

MALICIOUS

PDF

95.2 KB Created: 2021-03-29 02:11:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: d96c0a4ec08317b2befc7c4d3b78ade6 SHA-1: eb16ef76a8214c8fd0696af40bc88ce6f3fafcfa SHA-256: 3bcd88d9e520f09b71e0e600485b52553fe651dbeb68eb94d8f01fc526c45fc7
244 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of embedded links pointing to external resources, many of which are hosted on disposable or suspicious domains. Heuristics indicate this is a link farm, likely for SEO manipulation or to distribute malicious content. The presence of a malicious redirector link and ClamAV detection further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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/award?keyword=brevet+2020+fran%25C3%25A7ais+corrig%25C3%25A9+pdf In PDF document text
    • http://dibiwarisogix.mygamesonline.org/ethiopian_orthodox_amharic_bible.pdfIn PDF document text
    • http://nanamojuvimujo.medianewsonline.com/geological_strength_index.pdfIn PDF document text
    • http://pakupuxojopef.getenjoyment.net/bofrost_katalog.pdfIn PDF document text
    • http://gekifek.scienceontheweb.net/badminton_court_measurement.pdfIn PDF document text
    • http://tideboweped.medianewsonline.com/20795360417.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/b222a606-8244-4490-979f-98c3453bfa86/40634729426.pdfIn PDF document text
    • https://s3.amazonaws.com/gawabog/39680718364.pdfIn PDF document text
    • http://tipipigi.atwebpages.com/tobakilejuzebexeropovexa.pdfIn PDF document text
    • http://zusaxadixuxot.myartsonline.com/asp.net_mvc_full_stack_developer_interview_questions.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/83c158fd-a8a0-48d6-bad4-aa9c644520f6/libatesazivedepugo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/81df8f57-9412-4101-872c-3886f4db4772/gewulitibadoxirero.pdfIn PDF document text
    • https://s3.amazonaws.com/sixolose/icmr_guidelines_for_pregnant_woman.pdfIn PDF document text
    • https://19004eff-8f5e-45b0-b15a-9fbdbd99e39d.filesusr.com/ugd/578ea4_b1b1061a76754865a2122d11f4881c61.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/mogedozara/biglietti_da_visita_fai_da_te.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a673c12f-3ea5-4d11-bbf7-cf36d7c69aa4/how_to_install_mobile_home_furnace.pdfIn PDF document text
    • https://11ab4cf5-156d-4417-99e9-5039b2a7eb5f.filesusr.com/ugd/82d61e_89532fde5b04496791d259c40db88d51.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/21b1fbbe-1c5f-4385-a11e-36bbd3fe52d3/the_moral_landscape_review.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/28f616bd-4d8a-4810-8cf2-2022e9938cb0/how_to_know_if_nest_thermostat_is_working.pdfIn PDF document text
    • https://s3.amazonaws.com/risisipajole/school_annual_day_report_ppt.pdfIn PDF document text
    • https://s3.amazonaws.com/negonanopix/74510675781.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4ee1cd9e-3e65-48bd-9a0f-256524dd9c99/66244235400.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4c4254eb-db62-4761-a64f-fc457784d33d/81848355384.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010dd5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DD5 5784 bytes
SHA-256: ad5559c5453eecb28f0f1acf32c7d5d76cbbd552b10dbadb41b658852cd68354
font_01_sfnt_off00012109.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12109 13036 bytes
SHA-256: f199bf42fed8fd4f36b6b3e071324c40f45955d06cdbb035bafaca48c0d8ceb0
font_02_sfnt_off000149d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x149D4 16232 bytes
SHA-256: 1d4ebd634e9a4b1afc3ba2e660f7abdbad7ecfb3c20c2fb0daf688bec4f9a1d5
font_03_sfnt_off00015ef0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15EF0 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333