Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d721befd8519830…

MALICIOUS

PDF

84.1 KB Created: 2021-09-19 14:48:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 5788381280e62aede962741f2a005b6e SHA-1: 94ddcaf668ae26da252b8ef61cb046158e49c09d SHA-256: 8d721befd8519830fdf34464366abdcfff12961c79760cc480373876fd08686a
146 Risk Score

Malware Insights

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

The PDF document was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The 'SE_CALLBACK_LURE' heuristic strongly suggests a callback phishing or tech-support scam pattern, where users are prompted to call a number for fake issues. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a phishing or malware distribution attempt, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 https://synerhu.ru/uplcv?utm_term=how+do+i+play+music+stored+on+my+android+phone PDF link annotation
    • http://daisytalavera.com/userfiles/files/52257273594.pdfIn PDF document text
    • http://pxmonastery.org/CKEdit/upload/files/51009070879.pdfIn PDF document text
    • https://www.tahitotfalu.hu/ckfinder/userfiles/files/3424062712.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138422cee662---fabunuji.pdfIn PDF document text
    • http://thegioituigiay.net/uploads/files/gibawil.pdfIn PDF document text
    • https://shoppingplanet.ro/ckfinder/userfiles/files/velinekolumobixemu.pdfIn PDF document text
    • http://secureyun.cn/uploadfile/file///2021091908000213.pdfIn PDF document text
    • http://adice-area.com/pictures/files/31840386652.pdfIn PDF document text
    • https://martabaktelor.com/contents/files/ximifipizotowawete.pdfIn PDF document text
    • http://architettotamborra.eu/userfiles/files/99131618263.pdfIn PDF document text
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/65f0df335aa46e5ffbf0ed4198934708/14630923826.pdfIn PDF document text
    • http://lblussana.it/images/file/kidirutuxaxasawizijo.pdfIn PDF document text
    • http://hsound.ro/images/custom/file/muwekevidavuxefusaten.pdfIn PDF document text
    • https://livre-d-art.com/ckfinder/userfiles/files/jafije.pdfIn PDF document text
    • http://gordostcrista.ru/userfiles/file/dozogatovexelibobivabokin.pdfIn PDF document text
    • https://superlitefan.com/uploads/files/dagiwuvozojujanakadop.pdfIn PDF document text
    • http://udokutscher.de/gfx/userfiles/files/62097287375.pdfIn PDF document text
    • http://www.sosonomo.com/ckfinder/userfiles/files/sikavofebemivofumona.pdfIn PDF document text
    • http://kenzoum.org/home/integrity/public_html/ckfinder/userfiles/files/zufamakofelej.pdfIn PDF document text
    • https://camphacement.vn/upload/files/kuxaluvonoge.pdfIn PDF document text
    • http://studiolauramoschini.it/userfiles/files/zegatigufiwaxajelitam.pdfIn PDF document text
    • https://jlgardner.org/home/jlg/public_html/ckfinder/userfiles/files/95435123200.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_off0000e209.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE209 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fa1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA1B 18136 bytes
SHA-256: 8373e5553ce5c9c133ba7bebb1ef7686930ff2683a953c22a1cd04b39571834c
font_02_sfnt_off0001292b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1292B 11072 bytes
SHA-256: 94674be8acce7974289aaf991fdc4b47f544a71a1b550f06dfa02ebf514a8ed8