Malicious PDF — malware analysis report

Static analysis result for SHA-256 3cd8ed5d008ca8d3…

MALICIOUS

PDF

74.0 KB Created: 2021-09-19 07:18:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 53ea2d44d5ea7e9c13857a39cc7b5f34 SHA-1: e13c9fdc4b3d4baf17ec6f27d7eec0e7be999d00 SHA-256: 3cd8ed5d008ca8d377808b128da431cbc91cda86c9d269e2313d373b1184ee2b
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links to external resources, including one identified as a PDF file, suggesting it's part of a phishing or malware distribution chain. The 'SE_CALLBACK_LURE' heuristic indicates the document's content is designed to prompt the user to make a phone call, a common tactic in callback phishing and tech support scams. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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 link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://allytemp.ru/uplcv?utm_term=audio+book+apk PDF link annotation
    • http://sinosteelcode.com/filespath/files/20210910144808.pdfIn PDF document text
    • http://electriccityusa.com/images/fck_uploads/file/xujixisozu.pdfIn PDF document text
    • https://www.solucionaesp.com/ckfinder/userfiles/files/6841756922.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/c18a30e96b9136312acbece986e5805a/44156888710.pdfIn PDF document text
    • http://prasongp.com/file_media/file_image/file/76588717028.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/qk800m5r0ecvrvit6c284n5ro3/17064644012.pdfIn PDF document text
    • http://hanaelectric.com/userData/board/file/suzakavosawobene.pdfIn PDF document text
    • https://cryptoshift.be/anaeter_capital/siteadmin/userfiles/files/kuwalujirumezune.pdfIn PDF document text
    • http://kengosushionlineorder.com/uploads/files/27622942010.pdfIn PDF document text
    • http://studiorapizza.it/userfiles/files/velibowutizivimirad.pdfIn PDF document text
    • https://yasacompany.com/upload/files/turufexanotuzos.pdfIn PDF document text
    • https://curvy.tw/upload/files/55982535811.pdfIn PDF document text
    • https://csmgh.net/pevron/www/img/file/kunomexijekakegikawozi.pdfIn PDF document text
    • https://sandp-engineering.com/ckfinder/userfiles/files/nadamases.pdfIn PDF document text
    • http://ambulatorioveterinarioilghirlandaio.it/userfiles/files/gamobito.pdfIn PDF document text
    • http://www.arborvitae.cz/ckfinder/userfiles/files/15913297929.pdfIn PDF document text
    • http://capmar.eu/userfiles/file/21642680070.pdfIn PDF document text
    • http://take114.kr/FileData/ckfinder/files/20210902_3665BC7C3B91422F.pdfIn PDF document text
    • http://burattinojatek.hu/userfiles/file/39084041357.pdfIn PDF document text
    • http://master-sign.ru/ckfinder/userfiles/files/34434233126.pdfIn PDF document text
    • https://residenciasanamaro.es/userfiles/files/duzutematugofetafonikita.pdfIn PDF document text
    • http://theprojectmanagement.guru/cote_dor_import/admin/ckfinder/userfiles/files/45565020655.pdfIn PDF document text
    • http://zhouzhuanx.com/v15/Upload/file/2021913015383316.pdfIn PDF document text
    • http://5percent-design-action.com/upload/users/files/tazujikasemub.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c3e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dbfb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBFB 10048 bytes
SHA-256: 3df0676618f0f753bcf6aabddc1b4fe99ceafefaa27466c0e440fc0688707f7a
font_02_sfnt_off0000f224.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF224 16016 bytes
SHA-256: d98aa48f5c78a88a0904e714c132e2fb5989f5257928e9927636fb764cac1427