Malicious PDF — malware analysis report

Static analysis result for SHA-256 f1664caa4777b8b9…

MALICIOUS

PDF

87.8 KB Created: 2021-08-06 23:36:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 5ff5c34df9497033d924cad9ba639e63 SHA-1: 6f825dd934f757901f5afb2369f96436508de155 SHA-256: f1664caa4777b8b9115a88eac0d1ef8edbd349d59f0fb95ece07b6fa9f1d749c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. The sample also exhibits characteristics of a link farm, with numerous URLs pointing to potentially compromised websites or disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely to redirect users to phishing sites or download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16080cafe630c6---fororamefadogat.pdf In PDF document text
    • http://theemasternetworker.com/ckfinder/userfiles/files/zokevajor.pdfIn PDF document text
    • http://standardamulet.com/files/files/39307303369.pdfIn PDF document text
    • https://jagamimpi.net/contents//files/binoponorebuxezifu.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/04e4ca2277106f03f00cd0cec13a71a0/revaxomojiwegu.pdfIn PDF document text
    • https://www.ndgai.com/wp-content/plugins/super-forms/uploads/php/files/u4ls1ok4fh1kgfimue1l5jqjfo/gotosukajofinokopuze.pdfIn PDF document text
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607fc80ef4056---98591671798.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/16090928c598f8---gibed.pdfIn PDF document text
    • https://johanbjerke.se/userfiles/file/tejodi.pdfIn PDF document text
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609a9605b5f50---desisefozuzogokej.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e7cb5d69a5---segax.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/wadamurulofoj.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/731d048c799c700a578006851e61bacd/2342262590.pdfIn PDF document text
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/dbb209b000f8807d7f6196f071f7bfac/vofobijelatilasedesuze.pdfIn PDF document text
    • http://mundori.com/js/ckfinder/userfiles/files/3847690158.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/160a4ae056cf36---maxavi.pdfIn PDF document text
    • http://soflocops.com/clients/67403/File/39042939947.pdfIn PDF document text
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b10d88b1ff---venotigujo.pdfIn PDF document text
    • http://robotsuk.com/luckingbros.co.uk/userfiles/files/zadokirupowun.pdfIn PDF document text
    • https://angelsforwarriors.org/userfiles/files/76818513707.pdfIn PDF document text
    • http://108homed.com/userfiles/files/gaxubisowi.pdfIn PDF document text
    • http://perles-del-beya.com/userfiles/file/99088752274.pdfIn PDF document text
    • https://eitmedu.in/ckfinder/userfiles/files/95102314073.pdfIn PDF document text
    • http://caudafotografia.com/userfiles/files/4717953046.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=famous+quotes+from+all+the+bright+placesPDF 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_off0000f3ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3AE 16912 bytes
SHA-256: face5edb06ec3fcfcb366a7fd5caba5ef1e52e8d2b203563553a2f5fecdf130c
font_01_sfnt_off00011f7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F7C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013793.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13793 11188 bytes
SHA-256: c1dc1e5fc2e2578033277f10fcfe0810361e37e8a3bc3fc1fbf97a68c72804c2