Malicious PDF — malware analysis report

Static analysis result for SHA-256 78a4a9607c6cb3f1…

MALICIOUS

PDF

82.2 KB Created: 2021-09-15 09:43:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 7139cda45baedbfc5d1ebf27ad2be002 SHA-1: a16b2538b84cd0c6213154a6097ec8719d07750b SHA-256: 78a4a9607c6cb3f1e36569710ad44de86fe1dac7c750ec5b5f6aae3c176cd903
164 Risk Score

Malware Insights

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

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. It also contains a large number of URLs, many of which point to compromised CMS uploads or disposable hosting, forming a link farm. These elements strongly suggest the PDF is designed to redirect users to malicious sites, likely for phishing or to download further malware. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://pistant.ru/uplcv?utm_term=difference+between+spi+and+i2c PDF link annotation
    • https://dlt-nkp.com/fileupload/file/lejufekazu.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139bd8b7ebec---93836550753.pdfIn PDF document text
    • http://winhazel.com/indigo/ckfinder/userfiles/files/55058989863.pdfIn PDF document text
    • https://eurotig.ro/file/74846798600.pdfIn PDF document text
    • http://www.lalorraineperdue.com/documents/79593260171.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/j4ts29bo2egqegmqu32gkntuqf/terulunixawirewin.pdfIn PDF document text
    • http://capesociety.ca/uploads/files/7200502251.pdfIn PDF document text
    • http://rassadaspb.com/new/files/file/vaneridusiforavadom.pdfIn PDF document text
    • http://upoart.com/ckfinder/userfiles/files/nedelatamaveno.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16141923203cf3---nujogopiruzazojevo.pdfIn PDF document text
    • http://kalikraft.com/images/file/fikunolofomagaximenoke.pdfIn PDF document text
    • http://www.jasfec.com/imgs/uploads/36247368554.pdfIn PDF document text
    • http://romento.com/uploaded_files/userfiles/files/27790135558.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f1819a2b6b---xutuweroxovovuzisaxusuli.pdfIn PDF document text
    • https://mi-stores.com/basketballtotaal/images/editor/file/bipazafu.pdfIn PDF document text
    • http://gelateriacool.it/userfiles/files/15685649501.pdfIn PDF document text
    • http://timavoshipsupply.it/userfiles/file/budalep.pdfIn PDF document text
    • http://gearonlaw.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gisitajewodalepagoluj.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130959f7a6b9---93255428186.pdfIn PDF document text
    • http://precedent.by/_newsite/images_from_html_editor/file/tetagusinitide.pdfIn PDF document text
    • https://yuvasarkar.org/userfiles/file/mamudojufijogajezo.pdfIn PDF document text
    • http://architettogherardi.eu/userfiles/files/9395094397.pdfIn PDF document text
    • http://kurumakaitori-one.com/js/upload/files/74217285232.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_off0000dd46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD46 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f55d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF55D 10792 bytes
SHA-256: 4db542c1529f3b6d9af338e62bcc18865000b97daf111315a030a882f5671933
font_02_sfnt_off00010e48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E48 17296 bytes
SHA-256: 1ab06340dd6690e89578e5cab6de00f1df331e5aab16ae18a83a1b1420cd646e