Malicious PDF — malware analysis report

Static analysis result for SHA-256 21b889c043b9b3ee…

MALICIOUS

PDF

82.3 KB Created: 2021-09-19 04:04:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 73c7e021a600b5c0af5126cc10aa2f17 SHA-1: ba7365d671902b39945bbbe2698f5d357d00ae30 SHA-256: 21b889c043b9b3ee7dd0640e7ea50e7efe771dc7e756b460ca6e2a53e1f675bb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF containing numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the PDF structure itself facilitates the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

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://crysiq.ru/uplcv?utm_term=whyte+v+povetkin+free+live+stream PDF link annotation
    • http://sunpix.ru/img/lib/file/kobawefadaresageline.pdfIn PDF document text
    • https://jasmijnbloemengroen.nl/userfiles/file/wupazezer.pdfIn PDF document text
    • http://kmconlinecme.com/userfiles/file/33940665000.pdfIn PDF document text
    • https://aymsoft.us/aym_image/files/2282620696.pdfIn PDF document text
    • https://basisangka.com/contents/files/bumawujenofige.pdfIn PDF document text
    • http://mutamobilya.com/images_upload/files/sojivivadel.pdfIn PDF document text
    • https://fzclicks.com/demo/files/editor/file/todixumoku.pdfIn PDF document text
    • http://kirsanov-maslo.ru/uploads/54638652002.pdfIn PDF document text
    • https://mamap.in/ci/userfiles/files/rilajo.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146872d68203---kugaxufen.pdfIn PDF document text
    • http://mylodge-naoshima.com/images/blog/file/25477308629.pdfIn PDF document text
    • http://mgtofubbq.com/uploads/files/33028901015.pdfIn PDF document text
    • http://bertrandetgastineaudesigners.com/userfiles/file/93192942388.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e3dfa58cee---4350637754.pdfIn PDF document text
    • https://aarushimukhwas.idealviews.com/userfiles/files/12043866886.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/16141762f657ef---12385825375.pdfIn PDF document text
    • https://everywheregenes.com/uploadfile/qu26_qu106_com/files/64465520689.pdfIn PDF document text
    • https://greenbins.ca/ckfinder/userfiles/files/digasap.pdfIn PDF document text
    • http://madveras.com/ckfinder/userfiles/files/gitejoni.pdfIn PDF document text
    • https://inprovitbolivia.com/ckfinder/userfiles/files/7628491201.pdfIn PDF document text
    • http://www.thaiboat.net/image/upload/File/gonojemirisedu.pdfIn PDF document text
    • https://protradingindia.net/userfiles/file/56126494756.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_off0000d97f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD97F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f196.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF196 10888 bytes
SHA-256: cacece6795aef7c6dc6d0edf2555482487f0a48b5250d73bc735040b3d6fbd80
font_02_sfnt_off00010aa1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AA1 18548 bytes
SHA-256: 7e92ffc1baea02c8aab99af77b7da9f49925ab1db763f5ac407dcb683dd505b0