Malicious PDF — malware analysis report

Static analysis result for SHA-256 f540f719e9ff02ec…

MALICIOUS

PDF

86.2 KB Created: 2021-07-03 20:04:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2c72f388939b8be161137c0bb4d22386 SHA-1: 5a8073c02a05fcb4a54cde55adbff0129b153ef7 SHA-256: f540f719e9ff02ec23dfced5768524b4f1e6945d7f9cebb5ce7408160e742f1f
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress upload directories, indicating a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly suggest malicious intent. The document's structure and embedded URLs are consistent with attempts to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16089b5d494e6c---tonixemojowikadekilov.pdf
    • http://northcity.rs/slike/files/35378222888.pdf
    • https://abugfreemind.com/userfiles/file/binix.pdf
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/17efbe1caa14b012274d57a5800f2d93/99751558783.pdf
    • http://www.urbanwaterways.info/files/10516479118.pdf
    • http://synergyproperty.com/images/files/wunalonusefifusikebat.pdf
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b23a390ab53---70909762103.pdf
    • https://ilc.ua/wp-content/plugins/super-forms/uploads/php/files/dhgp0es4ksa2vbeecm32rgi7i0/lunikiximekujibukewozug.pdf
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/590d159f8ae00adc6c05cb540f7d15d7/41426065180.pdf
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/h91soi9fijbtacmspk06abu2qe/jixikukel.pdf
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/5dbe6fa11a6edbac7b651c62a247b759/29787868901.pdf
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078472a980c8---pajexolobirobepavesipifu.pdf
    • https://protectname.xyz/whoisprivacy/userfiles/files/kafolevomiwosagajat.pdf
    • http://stlnsk.ru/uploads/file/46166469556.pdf
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1607fd14ec0c1a---fevuzotonevonub.pdf
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085997dc9cd0---94752798342.pdf
    • https://amadesafar.ir/basefile/amadesafarir/files/83057725215.pdf
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/16075874480e69---45163640379.pdf
    • http://absolutelyneon.com/userfiles/file/ronemusagixawadam.pdf
    • http://hongshengfish.com/uploadfiles/2021070320184239552.pdf
    • http://msiutilities.biz/documents/87630625200.pdf
    • https://www.helpforbusymums.com/wp-content/plugins/super-forms/uploads/php/files/99c379e3be0077132039db4919cff267/duxuna.pdf
    • http://myredm.ru/uploads/file/dibotulifeme.pdf
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607c380ab9b62---vijalas.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=other+words+for+die
    • https://sharpspringwww.kinsta.cloud/wp-content/plugins/super-forms/uploads/php/files/3096d26e8b0c96dfeed00dc0f298db53/pedoj.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f01e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF01E 16792 bytes
font_01_sfnt_off00010835.bin
c38d870f4af17346db87c49d60102203d481a91e08b1a7a37c12102812e0750e
pdf-font-stream PDF embedded font (sfnt) at offset 0x10835 10248 bytes
font_02_sfnt_off00011f76.bin
6c1273da68b20f1b11f5fb6a04780b2ad37eb54357334b5d67311224a50114a5
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F76 16904 bytes