Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd13fe4eae36a1b3…

MALICIOUS

PDF

89.7 KB Created: 2021-07-26 03:04:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 98e2947335f0d42d3262e6cec6553f52 SHA-1: f223feff7dd38ffdf6fa0203743e2aceada05a47 SHA-256: cd13fe4eae36a1b3c0317f7d0e64426039ff0ac3be12944cbac99aea0ae564e5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains a large number of links pointing to compromised WordPress upload directories and other disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. While no scripts were explicitly extracted, the structure suggests it's designed to lure users to external malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://winso.tw/userfiles/file/75139513517.pdf
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071f9485740d---33672601121.pdf
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16098ce0b880f0---pekavoxobuletuga.pdf
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608bb3ab228ed---21885921263.pdf
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/fb334b328c735ea309ca7bfd00ddc9b1/2401135916.pdf
    • http://ridendo.cz/files/file/suputupakakete.pdf
    • http://gentlemensquartersbarbershop.com/wp-content/plugins/super-forms/uploads/php/files/80238c5f2f5c503efd22d1bbaf9fa44b/21495436627.pdf
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/e324e208e06b66a9ca116d369f76d27b/67225393606.pdf
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607eff0f5c95d---sebolunomibojonatifazo.pdf
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/437b7b62cb5ab781c27229e260ac67f7/najakegidokuditaxok.pdf
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/d4129bd02e0a87f1a86a392afdc4b526/57455057689.pdf
    • https://juvelyrikoscentras.lt/Files/file/41713867897.pdf
    • https://zegabilisim.com/calisma2/files/uploads/vojiwixubepope.pdf
    • https://kantankacreative.com/wp-content/plugins/super-forms/uploads/php/files/ab513a574a8d5ad2db3234b07b257eb6/vigegudupewipa.pdf
    • http://iphysiology.ru/upload/37090895008.pdf
    • https://www.asahinadigital.com/wp-content/plugins/super-forms/uploads/php/files/2q6nii83tstf2qirabmnmn6f16/73288087273.pdf
    • http://scenekunstskolen-efteruddannelsen.dk/ckfinder/userfiles/files/27926337799.pdf
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609590d922a55---vevisedudofaduzadani.pdf
    • http://b-solutions.net/userfiles/file/41896072792.pdf
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160853749554c5---1435235617.pdf
    • http://changju-hotel.com/CKEdit/upload/files/miwusabigim.pdf
    • http://sghscsjamarai.org/guruhargobind/userfiles/file/52657786940.pdf
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f954edaa760---76572181774.pdf
    • https://svetpoznaniyaonline.ru/wp-content/plugins/super-forms/uploads/php/files/e298ccef93e802db8e716d26267ae44a/gafutotolojamed.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=example+of+exchange+relationship
    • 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_off0000f92e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF92E 16792 bytes
font_01_sfnt_off00011140.bin
d23fb3438010eba8c0615dd3627cf2d2095b36e730d4ac7746c89e7c351099e2
pdf-font-stream PDF embedded font (sfnt) at offset 0x11140 18004 bytes
font_02_sfnt_off00014003.bin
ff25270829d086570bcdfcf74a299ffb138245f1d6dd8c868b17a3398eb50fe4
pdf-font-stream PDF embedded font (sfnt) at offset 0x14003 11012 bytes