Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ad35ce727e91db6…

MALICIOUS

PDF

81.7 KB Created: 2021-09-15 23:00:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 6ef9c3fe81ff1877c9b67504bf98b73d SHA-1: 37982f9b3c71b73735ea02ab3188949f9d6cf49c SHA-256: 4ad35ce727e91db69c017032af16d241091be58e3960fcb6e2b7f6414dd34fb2
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The presence of a ClamAV detection for 'Pdf.Phishing.Trojan' and a high ML classifier score strongly suggest malicious intent. The document body is heavily obfuscated, but the heuristics point to a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 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.
  • 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=life+of+pi+final+scene PDF link annotation
    • http://kxxbs.com/uploadfiles/file/a/95885375403.pdfIn PDF document text
    • https://ewt.cz/res/file/81304333243.pdfIn PDF document text
    • http://carbonelite.ru/file/bowowiwerekisefokoba.pdfIn PDF document text
    • http://ville-dammarie.com/ckfinder/userfiles/files/44552583648.pdfIn PDF document text
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/d230d2fe10892ddffa570821098e6566/muxidovurulox.pdfIn PDF document text
    • http://sake2metustin.com/uploads/files/65745221422.pdfIn PDF document text
    • https://nenmongdangquang.com/upload/files/tetux.pdfIn PDF document text
    • http://festacreativita.org/userfiles/file/65355109044.pdfIn PDF document text
    • http://tbm-mova.by/images_from_html_editor/file/fukibaboxuxilinisikajore.pdfIn PDF document text
    • https://avistravel.ro/userfiles/file/21836663469.pdfIn PDF document text
    • https://altstudio.be/app/webroot/uploads/file/pifudinone.pdfIn PDF document text
    • http://www.ondebiz.com/userfiles/file/36681052637.pdfIn PDF document text
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16135658dc4ffa---14222380156.pdfIn PDF document text
    • http://velapower.com/glwh/UploadFile/file/2021090111093873499.pdfIn PDF document text
    • http://hoteldarim.ir/basefile/hoteldarimir/files/62074301994.pdfIn PDF document text
    • http://galluccifaibano.com/userfiles/file/nevuxukufetesalox.pdfIn PDF document text
    • https://flardochform.se/userfiles/file/werijexikenejebuwinikid.pdfIn PDF document text
    • http://nktrading.qa/file/files/dimibuxelarezotupunetoto.pdfIn PDF document text
    • http://bluebirdcanada.com/FileData/ckfinder/files/20210902_8B614B5CA34AC895.pdfIn PDF document text
    • http://uniradioweb.info/userfiles/file/65697502339.pdfIn PDF document text
    • http://happyland-nsk.net/ckfinder/userfiles/files/perufamekosaged.pdfIn PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/c2ae2333463b062f922c1d9da1fe4261/32588128328.pdfIn PDF document text
    • http://www.polni.si/Images/files/73437599255.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_off0000dcf3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCF3 10232 bytes
SHA-256: 052bbf747e3d757764c6cc1205b79574471828feb2b1e32d85eaf8daffdc6ea6
font_01_sfnt_off0000f403.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF403 17428 bytes
SHA-256: 68c9a03f23d1c27ff34a99a43f65cb3a5acba29daf136cbfe486871c0c63c2d8
font_02_sfnt_off00012157.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12157 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1