Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7da2f67cf1db747…

MALICIOUS

PDF

74.4 KB Created: 2021-06-09 23:04:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 23cdc060b595637467342487f4745291 SHA-1: 03dc9adc3322ea1291b5b8edf428c4053849cdf2 SHA-256: b7da2f67cf1db747e8dad80a4e38318b214b95ba6e9e0d41dd8a6303ded4d50a
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, identified as a link farm, with a primary URL pointing to a site that appears to be part of a SEO spam or phishing campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest it's designed to redirect users to malicious or spam content.

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://coretry.ru/pbw?utm_term=synthetic+division+of+polynomials+worksheet PDF link annotation
    • https://vebifejelib.weebly.com/uploads/1/3/0/7/130775119/e9a6b2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453740/normal_6068ec3eaff07.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4470017/normal_5fce632a45ec5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369141/normal_60c0486a61ff3.pdfIn PDF document text
    • https://vutuwibomakupir.weebly.com/uploads/1/3/2/7/132740747/15ba08e254.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417535/normal_6022a9ec20265.pdfIn PDF document text
    • https://gemajoxow.weebly.com/uploads/1/3/4/7/134721961/gupadelijavupexux.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4480142/normal_5febcd8a7288a.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://kipizasuzeda.pbworks.com/w/file/fetch/144586143/pojirezipujojarogozi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f4b2369d-f046-4026-b137-4a59ae5b80dc/hamilton_beach_air_fryer_toaster_oven_manual.pdfIn PDF document text
    • http://gafuxexosaru.pbworks.com/w/file/fetch/144898320/parexilopisawopija.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/395b41cd-f565-44a3-981f-878ce7ec0d02/what_is_the_definition_of_reproduction_in_biology.pdfIn PDF document text
    • http://dawijunegolo.pbworks.com/w/file/fetch/144569757/31548854789.pdfIn PDF document text
    • http://lekipirunezi.pbworks.com/w/file/fetch/144415863/59019903479.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/73eafc62-4ac0-4612-8009-72e99347e84a/should_you_keep_clothes_that_dont_fit.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e4624be9-4292-4c1a-8d3b-a6e7d0fd688a/how_to_fill_out_a_receipt_book_from_staples.pdfIn PDF document text
    • http://mitamugukojo.pbworks.com/f/kexukugenobel.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5f854160-2cd6-4716-bfd5-6db5b86eed70/do_wagner_paint_sprayers_work.pdfIn PDF document text
    • http://pefumugat.pbworks.com/w/file/fetch/144590232/what_schedule_is_class_150_pipe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4f8d1cd9-3e1f-4fd3-a16f-b5800647636b/enfermedad_q_duele_todo_el_cuerpo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a692af04-f6cc-484b-9c47-5ce90174b7e9/thermador_range_error_code_55.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_off0000e479.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE479 5816 bytes
SHA-256: 28938b071e0270dfb0c8895a97c9cc87e070906f4520d9f67d9bad8fa488b40f
font_01_sfnt_off0000f83a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF83A 10388 bytes
SHA-256: 6703df1b865f690825aab7b74b9e5c84751c053a48ec9ebd43d01255e3209396