Malicious PDF — malware analysis report

Static analysis result for SHA-256 03853d46e5b52c4d…

MALICIOUS

PDF

74.9 KB Created: 2021-09-18 15:45:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a4bd54d902fd0585d0e44cbd21df3f78 SHA-1: 9f3b2e02384c54c0e4593d5c08fdfebff5f2843c SHA-256: 03853d46e5b52c4df4b73e94597d9f43878f71eb517a52f80c65bb4e49bde1cf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple external PDF files hosted on various domains, some of which are compromised CMS uploads. This suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://kleinschadenexpert.de/userfiles/file/sopiwemezofaja.pdf In PDF document text
    • https://alquimia.in/admin/fckeditor/editorfile/79298340194.pdfIn PDF document text
    • http://spadhotel.com/basefile/spadhotelcom/files/rekilesubi.pdfIn PDF document text
    • https://istanbulbalbir.com/upload/ckfinder/files/44846469065.pdfIn PDF document text
    • http://bacvietexpress.com/upload/userfiles/files/78821451428.pdfIn PDF document text
    • http://professional-tuner.at/uploaded/file/69077085462.pdfIn PDF document text
    • https://huanghecables.com/d/files/vonowaborupodupoxe.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/lozaponimi.pdfIn PDF document text
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/fde4e4f9c87d9417cae71cb476d0ebf1/mazawarudadazotiw.pdfIn PDF document text
    • https://atcotourismtravel.com/userfiles/file/janibulosakudukaru.pdfIn PDF document text
    • http://chekeeh.ir/basefile/chekeehir/files/fivavomomenimom.pdfIn PDF document text
    • http://ckrestaurantgroup.com/ckfinder/userfiles/files/9771212349.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/1a2726cece3b87eec30a3871d2818555/76071260249.pdfIn PDF document text
    • https://demo-calson.garment-pro.com/ckfinder/userfiles/files/92715786361.pdfIn PDF document text
    • http://stfurnimart.com/file_media/file_image/file/gebeditumuruteledinasage.pdfIn PDF document text
    • https://globalcircle.club/userfiles/file/36812131979.pdfIn PDF document text
    • http://harchovyk.com/userfiles/file/detemufusajoludixagojoka.pdfIn PDF document text
    • http://xn--e42bt3l.net/upfile/files/36403243017.pdfIn PDF document text
    • https://copyjokertw.aw6.tw/uploadfile/qu4_qu106_com/files/18894015036.pdfIn PDF document text
    • http://dc-3ed4d7413bdb.prshots.de/uploads/userfiles/1630790627/files/29996433332.pdfIn PDF document text
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/bcvvhebodsg6u9075ml8kcvff1/wudulegajulumirujafutinew.pdfIn PDF document text
    • http://opuspoint.com/ckfinder/userfiles/files/72857641678.pdfIn PDF document text
    • http://sieuthivatlieuhoanthien.com/upload/files/jonububunadelez.pdfIn PDF document text
    • http://www.corazondelsol.es/ckfinder/userfiles/files/84930618594.pdfIn PDF document text
    • https://ngonluathan.vn/images/ckeditor/files/25176072334.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=azan+ringtone+mp3+downloadPDF 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_off0000bf20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF20 17428 bytes
SHA-256: bfc824836371245395f3a2ad3378c309b34c8ad4c1d889d869857b9bb585d760
font_01_sfnt_off0000ecc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECC1 10868 bytes
SHA-256: 7a67d520c41749fe60cbea5dac7c4f0b8ac480e8d8f6d692f66e88a2d14fc7f8
font_02_sfnt_off000105bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1