Malicious PDF — malware analysis report

Static analysis result for SHA-256 805a5ca1ac64340b…

MALICIOUS

PDF

89.6 KB Created: 2021-09-15 21:15:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 8c8d672c1ac627c5e58a59803ea4a6d7 SHA-1: dd0510f6be9d9ef1d1ac4133e979ab731147c8a0 SHA-256: 805a5ca1ac64340bc192ce135d7211bac6f3d523edd3f0f1e4cc945a0d91468c
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a callback phishing lure. The document body is heavily obfuscated, but the presence of numerous embedded URLs and the 'SE_CALLBACK_LURE' heuristic strongly suggest a social engineering attempt to trick the user into calling a fraudulent number. No scripts were extracted, but the overall structure and heuristic firings point to a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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
  • 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 http://phantasos.org/userfiles/file/52794073058.pdf In PDF document text
    • http://rentaruedas.com/files/others/38019699110.pdfIn PDF document text
    • https://avukatwebsitesi.trakyasoft.com/upload/files/64748882552.pdfIn PDF document text
    • http://school19-zav.ru/userfiles/file/62724590756.pdfIn PDF document text
    • http://bastola.org/userfiles/file/giwekelixifuxizojidili.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/c17ea514819a83eb036428b303a0b442/dogofopazuxuketeg.pdfIn PDF document text
    • https://ystechpro.com/nbloom/fckuploads/file/57956310437.pdfIn PDF document text
    • http://infoguard.ru/content/file/pusuxirososim.pdfIn PDF document text
    • http://air-con.ru/upload/files/laxejekesixatunerev.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138f819dceb8---gubesixalupuruwineru.pdfIn PDF document text
    • https://unitytradecapital.com/ckfinder/userfiles/files/zexikiverozamokuxoxusodi.pdfIn PDF document text
    • http://revize-elektro.info/UserFiles/File/77944488281.pdfIn PDF document text
    • http://yhbinternational.com/userfiles/file/rokala.pdfIn PDF document text
    • http://debeleven.net/UserFiles/File/7114574676.pdfIn PDF document text
    • https://next-engineering.com/userfiles/files/zupogodutafodam.pdfIn PDF document text
    • http://mwbright.com/upload_fck/file/2021-9-12/20210912090200460330.pdfIn PDF document text
    • http://novafish.it/userfiles/files/luxazikasexabonikaduf.pdfIn PDF document text
    • http://matras-devison.ru/upload/file/93228097193.pdfIn PDF document text
    • http://stfurnimart.com/file_media/file_image/file/44576278161.pdfIn PDF document text
    • http://jawarakreasi.com/file/pufudekigovi.pdfIn PDF document text
    • https://greenboo.vn/uploads/files/dorufowinetupa.pdfIn PDF document text
    • https://hijaustabilo.com/contents/files/memijijepamikudof.pdfIn PDF document text
    • http://china-engine.net/ckfinder/userfiles/files/wemudeveturalovonepe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=how+to+tell+if+your+phone+has+been+compromisedPDF link annotation
    • 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_off0000f90b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF90B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011122.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11122 11316 bytes
SHA-256: 8d413f5d6146148a356d97a990135c7ac3e3b66a8eef60d181f951a24d6a5a42
font_02_sfnt_off00012b5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B5C 17568 bytes
SHA-256: bc66c23608fa932f6e33e2a651bce21f5e7336f728b52950a1c471c8850cb843