Malicious PDF — malware analysis report

Static analysis result for SHA-256 d85dcf3a750d9fc3…

MALICIOUS

PDF

76.0 KB Created: 2021-09-17 10:54:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8835599e7ea09e93b87ed5ab5958aa72 SHA-1: ff8ecf25c9a4a905724bb3f47a41c909920df6c5 SHA-256: d85dcf3a750d9fc3a02b355562d9e72167f60dae38c7e27c98939d5cb3fefa4f
156 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous external URLs, many hosted on disposable domains or compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The document body is unreadable, but the heuristics point to a deliberate attempt to redirect users through a network of links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://www.shipgo17.com/plugin/ckeditor/ckfinder/userfiles/files/wuwugaxovapufize.pdf
    • https://namkhoasaigon.vn/web/images/files/28835904304.pdf
    • http://lisaarkin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/neromebaramegijorogofirib.pdf
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/161352ba5bec1e---wekegodapuwisuxan.pdf
    • http://hsaltsj.com/uploads/files/6398582489.pdf
    • http://avvocatoandreabruschi.it/userfiles/files/pawotuxomiwakewos.pdf
    • http://www.anjhimayath.com/upload/file/gotiwodorobokopinumup.pdf
    • http://tinavaron.com/ckfinder/userfiles/files/begemus.pdf
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c7aa1b4847---89404009491.pdf
    • https://cartolmania.it/file/64997135022.pdf
    • https://saksisan.com/upload/ckfinder/files/somutumuvemazuvonokodanev.pdf
    • http://bergepkolcsonzo.hu/userfiles/file/zibijobofopiloniliku.pdf
    • http://elverum-revmatiker.no/images/file/nuwudegolukovivuf.pdf
    • http://gemwishrs.com/ckfinder/stones/files/90554675937.pdf
    • http://recrute.fr/files/files/85004772827.pdf
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141751918af5---98224197675.pdf
    • http://rsst77.ru/upload/files/zikirokabopamun.pdf
    • http://citranco.com/users/files/walobiludezutexegate.pdf
    • http://massageindex.nl/images/uploads/sajewagolukak.pdf
    • http://rockycheng.com/ckfinder/userfiles/files/53459035877.pdf
    • https://iwistw.com/upload/files/midukuxiwin.pdf
    • http://hublihorse.com/uploads/userfiles/files/pemereligodepetazukimagi.pdf
    • http://videotour24.com/data/fckupload/file/zuloro.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=tagalog+words+that+starts+with+letter+c
    • 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_off0000c1a8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC1A8 16792 bytes
font_01_sfnt_off0000d9bf.bin
b2514326cb28d553435f1c437c9f240bb5872c8aac6831134b3d38314c184a66
pdf-font-stream PDF embedded font (sfnt) at offset 0xD9BF 10596 bytes
font_02_sfnt_off0000f1f5.bin
0df5c4bdf3c5c567d42f939e489313eb558581238736b970728ddaa539b9bbc9
pdf-font-stream PDF embedded font (sfnt) at offset 0xF1F5 18396 bytes