Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8fdfc8b4be9f1b1…

MALICIOUS

PDF

75.3 KB Created: 2021-04-03 14:24:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 6c5b731d2c191b7d109cdf97444883d1 SHA-1: d1cd32815c027beafd2eb769ef9cbdeec1e1b448 SHA-256: a8fdfc8b4be9f1b1c6d1f5a81c956949a5b33d7b82f3baceaaadb460663a1561
244 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many pointing to disposable domains and redirectors, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and numerous external links are indicative of a malicious redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://yafferge.ru/strik?utm_term=does+g29+work+on+pc In PDF document text
    • https://cdn.sqhk.co/zitibidino/jH93hib/timiwosaguro.pdfIn PDF document text
    • https://mawikimame.weebly.com/uploads/1/3/4/2/134235565/9531740.pdfIn PDF document text
    • http://vofidiporalives.22web.org/business_management_textbook.pdfIn PDF document text
    • https://putofikanavo.weebly.com/uploads/1/3/0/7/130738484/306588262521.pdfIn PDF document text
    • https://nodejobirutita.weebly.com/uploads/1/3/4/7/134748641/1352554.pdfIn PDF document text
    • https://piwofenuxud.weebly.com/uploads/1/3/1/8/131871692/09363b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4381294/normal_5fc8b23a6f109.pdfIn PDF document text
    • https://cdn.sqhk.co/depadukat/qjchdhi/29694500696.pdfIn PDF document text
    • https://pilorixo.weebly.com/uploads/1/3/4/6/134689004/nolon.pdfIn PDF document text
    • https://cdn.sqhk.co/xusorawoka/jwb4cYV/blank_boggle_board_template.pdfIn PDF document text
    • https://cdn.sqhk.co/sirijunubi/u3Kqgea/javubowilanutosokij.pdfIn PDF document text
    • https://cdn.sqhk.co/wekaradukuve/aU7fXuI/download_mega_man_3_mobile.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4378846/normal_604026196d4f4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4377101/normal_602c5cecf36d9.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://77da94c0-0f0a-445b-87af-e489a0b5ef66.filesusr.com/ugd/db1da1_eafe718303e64eaea45232e3ae291bfe.pdf?index=trueIn PDF document text
    • http://donaweraketo.rf.gd/algoritmo_cube_rubik_mirror.pdfIn PDF document text
    • http://rusilip.rf.gd/estimate_decimals_worksheet_with_answers.pdfIn PDF document text
    • http://patisex.rf.gd/canon_printer_error_code_p07.pdfIn PDF document text
    • http://fabodatutowew.epizy.com/cigna_international_dental_reimbursement_form.pdfIn PDF document text
    • http://julajig.rf.gd/36069344304.pdfIn PDF document text
    • http://sejabozewilobog.epizy.com/ampex_440c_manual.pdfIn PDF document text
    • http://penalat.rf.gd/android_phones_under_8000_samsung.pdfIn PDF document text
    • https://6cdb29d4-22ce-4aaf-9e51-562b59d50851.filesusr.com/ugd/1b20fb_182eb0cac2d24b488934355f12ccab03.pdf?index=trueIn 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_off0000e7ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7EA 5300 bytes
SHA-256: a4e9a4fb0f7cf76ddb889fe8ad83693659f42bbf8ae6034ba47a5bee2b44b554
font_01_sfnt_off0000fa2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA2F 10988 bytes
SHA-256: 6595623fce108349b6d1347ca63ff3bd3a6c1421e54d22b1a24c31ee7eb16e97