Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef51c7869cc78adc…

MALICIOUS

PDF

75.1 KB Created: 2021-09-18 18:02:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6fd19e396b248b8cfd52f016ea7a7878 SHA-1: bcf7f7cf28b95eab546d228d1dc3b248da94d7b5 SHA-256: ef51c7869cc78adc840dbea6d2d8d3fbb26e57fbc0b22f602b2ff4bd6e280666
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to websites hosted on compromised CMS platforms or utilize disposable hosting, suggesting a phishing or malicious redirection scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://entrackintl.com/uploads/somedog.pdf In PDF document text
    • http://nwhouse.ru/uploads/file/mitopisaguzotodixixuvav.pdfIn PDF document text
    • http://vetcasatenovo.it/userfiles/files/bavuwanuf.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/okh72oeclt98ptg2fn7pl4qr87/66463527714.pdfIn PDF document text
    • http://kramor.bg/userfiles/file/kuvizetijosibisod.pdfIn PDF document text
    • http://codemessaging.net/ckfinder/userfiles/files/jeziwoxagom.pdfIn PDF document text
    • http://sxcec.org/userfiles/file/24343230720.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145c4c79ca05---71541410985.pdfIn PDF document text
    • https://hpx.com.ua/wp-content/plugins/super-forms/uploads/php/files/5da902e19742adf550696a56a04e684f/51433298388.pdfIn PDF document text
    • https://bor-diing.com/upload/files/15205284291.pdfIn PDF document text
    • https://novamakine.com/upload/ckfinder/files/64666233222.pdfIn PDF document text
    • http://halongbaycruises.org/upload/files/66210928016.pdfIn PDF document text
    • http://live-lessons.net/lcj/web/uploads/assets/file/15477692455.pdfIn PDF document text
    • https://pointwebhost.com/calisma2/files/uploads/53954848454.pdfIn PDF document text
    • https://komunalno-vrgorac.hr/files/deramuvogagozunefavotarix.pdfIn PDF document text
    • http://omonetach.pl/foto/ilustracje/file/pebivobama.pdfIn PDF document text
    • http://logisticsnetworks.net/ckfinder/userfiles/files/97276974755.pdfIn PDF document text
    • http://onestep-tokyo.com/userfiles/file/66505902654.pdfIn PDF document text
    • https://hophamthaibinh.com/upload/files/67515944061.pdfIn PDF document text
    • http://harekatmemuru.com/images/Media/files/vakodolevetijalazegade.pdfIn PDF document text
    • http://www.cenlajobinator.com/siteuploads/editorimg/file/senubetekirob.pdfIn PDF document text
    • http://balbu.eu/uploads/news/file/25450360867.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=how+to+set+private+dnsPDF 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_off0000c316.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC316 16788 bytes
SHA-256: 2642fef5ec5274c9bbe057312c71929883986561ceee7e33160ce8ee59990793
font_01_sfnt_off0000eebc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEBC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000106d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106D3 10480 bytes
SHA-256: ac0292954f4160b91b649eb5d0cdfc504c299389f6c9c2fed6db6ae6ef0301eb