Malicious PDF — malware analysis report

Static analysis result for SHA-256 98b7773825ecda4c…

MALICIOUS

PDF

94.2 KB Created: 2021-07-18 21:28:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 163088a2bff93a5fb04c22a5f2d34145 SHA-1: 8350fd7f599bf632e7bf998b2a405c8c4194cbcc SHA-256: 98b7773825ecda4c1c2b26c85c4e8614f7d3f67cd582198e14b0930e8abf265c
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 compromised WordPress sites. Heuristics indicate this is a link farm designed to redirect users, and ClamAV detection confirms its malicious nature, classifying it as a phishing trojan. The ML classifier also strongly flagged it as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c47f6799191---juwokunixagixizetadokete.pdf In PDF document text
    • http://candybeauty.vn/upload/files/7753184774.pdfIn PDF document text
    • http://nickels.design/ckfinder/userfiles/files/sutizajuturukuduf.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/376325241029859894953723ae2a3521/19434867942.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/160747ce0ba136---xiwidasopeguzilage.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/5dd877912474eff43319477e73c0d4ca/likitokulizurovuw.pdfIn PDF document text
    • https://www.hotelamoha.it/wp-content/plugins/formcraft/file-upload/server/content/files/160943bdd7a43a---82868135230.pdfIn PDF document text
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/443f016977535fbedbd5f3b5f39f9bc7/melidifegudegavut.pdfIn PDF document text
    • http://falconfam.com/ckfinder/userfiles/files/88448779571.pdfIn PDF document text
    • https://interesttour.com/wp-content/plugins/super-forms/uploads/php/files/cbee09de9d5184b80f0fe816bf97f910/51791349388.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/vgmb5upq5tllspfek7n864khap/lizifopadixadabati.pdfIn PDF document text
    • http://saovietgroup.com/upload/FCK/file/lanoxoriramafopevudaxu.pdfIn PDF document text
    • http://marinapogon.pl/upload/file/29311627731.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/b3nb5ocrsbqbd6cv99png4tash/43773100118.pdfIn PDF document text
    • http://tatvideo.ru/ckfinder/userfiles/files/69952437529.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/a7ef84493c0a0ad4e0fccf89966eef7a/66599999010.pdfIn PDF document text
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/1qih4j1rp6h9ui2f14m567i3e1/kemazadibixuwatimifidomu.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/97iulv11egb0did3jnhvl6q712/35703576139.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/42592793364.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b14c1c5198---vepukujisafusixijuxinide.pdfIn PDF document text
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609466e731d15---43187225816.pdfIn PDF document text
    • https://szabobuszberles.hu/files/files/dowusamufevexugopubida.pdfIn PDF document text
    • https://tigercabinetry.com/wp-content/plugins/super-forms/uploads/php/files/df0ffda0104c6dd7bd8470fe38b5870e/sefavovelesatone.pdfIn PDF document text
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/8037d94ec823589bf86b85355d99e3d0/fedovibubagovivivemor.pdfIn PDF document text
    • http://coumert.com/images/file/28107505744.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=higher+education+interview+questions+and+answersPDF 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_off00010b82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B82 17768 bytes
SHA-256: 08dd41fd29164d87552edb9fbe468cab72880ba883cb574c12b092805bdac2b6
font_01_sfnt_off00013a28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A28 10992 bytes
SHA-256: 358cfc7db173ae0944423e633e4e889c994fbec75919fdcae090898d93ab8751
font_02_sfnt_off00015329.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15329 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1