Malicious PDF — malware analysis report

Static analysis result for SHA-256 790e3feea813b2f2…

MALICIOUS

PDF

74.0 KB Created: 2021-09-09 01:24:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 175a7345cd88a738460efeb1f75e443f SHA-1: f10a1faf132a226d417afbce01748b9762189720 SHA-256: 790e3feea813b2f27c31253a5e50e1a9c6e2dbb000e8f8d3dcfd5441c2e96dbe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1055.012 Process Injection

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Several heuristics identified the document as a link farm hosted on compromised WordPress sites, with numerous unknown URLs pointing to PDF files. The presence of these links suggests an attempt to lure users to malicious or phishing content, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16136008e40b02---najunofalaterejel.pdf
    • http://studiomilano.eu/userfiles/files/mugonutemiji.pdf
    • http://risme.vn/files/94415909406.pdf
    • https://optimustelecoms.com/ckfinder/userfiles/files/62572793443.pdf
    • http://vietsaovang.com/uploads/userfiles/file/muvaxov.pdf
    • http://pcccphucvinh.com/upload/files/33649910955.pdf
    • http://mitcostruttori.it/userfiles/files/tumeneraketefesupeke.pdf
    • http://brmhn.com/userfiles/file/20210904194839_esbnot.pdf
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/161386ecd5a7bf---7120580495.pdf
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/16132e4aebbda3---55736463068.pdf
    • http://www.jindatunnel.com/up_files/file/25062098280.pdf
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16135760268973---86842906154.pdf
    • https://pieseautocomenzi.ro/userfiles/file/22185691806.pdf
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f93d6d1a79---fupenowitizufuxogenoner.pdf
    • http://captaincook.hu/userfiles/file/rizibosufus.pdf
    • http://pantanalmsnews.com.br/ckfinder/userfiles/files/niwukojaxol.pdf
    • http://2017.letnifestiwal.pl/ckfinder/userfiles/files/97532325034.pdf
    • http://zopos.zohukum.com/ckfinder/userfiles/files/xekojejiluxufanuxunowo.pdf
    • https://led7.ru/file/43837588780.pdf
    • https://condominiovillage.com/userfiles/file/rupab.pdf
    • http://lejuriste.ru/files/file/sizefatitemaz.pdf
    • http://jyjwqj.com/uploadfile/file///2021090522135847.pdf
    • https://yumasri.com/assets/ckfinder/userfiles/files/3617232392.pdf
    • http://glttek.com/userfiles/file/54966576293.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=oval+button+android
    • 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_off0000baff.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBAFF 16792 bytes
font_01_sfnt_off0000d316.bin
ae4c5981f61afd339ef17d92e96290e1dc4be1e899ec5faa342b902e2ae99aee
pdf-font-stream PDF embedded font (sfnt) at offset 0xD316 10272 bytes
font_02_sfnt_off0000ea48.bin
a177d547c3bf71be83c150668b7615775b709e42715c6c02acdd2366d71df552
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA48 18052 bytes