Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c43f6fadfaa5dc7…

MALICIOUS

PDF

86.4 KB Created: 2021-08-14 03:03:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: cbe20511c3f5fe7545e4ab6a82f85e18 SHA-1: ba787875b97f5c3404338d9d6a04a8afcc3ca521 SHA-256: 6c43f6fadfaa5dc7e3f6dcee99bdc1fb75aa87dcf74502f3e4e6c731a44a3a5e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and contains embedded JavaScript. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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 https://unosms.us/userfiles/file/wudiber.pdf In PDF document text
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085b4493f530---gazisisuzigaxejuvexafaf.pdfIn PDF document text
    • http://wellfoto.cz/pictures/files/rajubivipexeworopa.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a67d0c98656---60876847799.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078da51d9176---konulixumokedebalifon.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160906401a1ada---6062636466.pdfIn PDF document text
    • http://qualityspices.in/ckuploads/files/67031890789.pdfIn PDF document text
    • https://marbellamohali.com/wp-content/plugins/super-forms/uploads/php/files/9bca7bd73b57cb4e1d23bc8f61c306ba/64716553118.pdfIn PDF document text
    • https://estigotours.com/wp-content/plugins/super-forms/uploads/php/files/415d866158321ae4c053ff8bdbd63daa/govemanuxekutenozegoziz.pdfIn PDF document text
    • https://gamedunyasi.com/calisma2/files/uploads/77078723474.pdfIn PDF document text
    • http://whuntex.ru/userfiles/file/fukibogawinuz.pdfIn PDF document text
    • http://geyikkimya.com/userfiles/upload/file/tutilinatiludukirokirozo.pdfIn PDF document text
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/d98c7f714dab6215a517471cbcf095d5/5652031494.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160f81e881f792---badimojeji.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608c4c047b6f1---77940848863.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d7a0b55fea4---rijefirutunijo.pdfIn PDF document text
    • https://asiahealthcaredentalcentre.com/ckfinder/userfiles/files/ledobolipuxuf.pdfIn PDF document text
    • http://www.tokyomagic.jp/images/library/File/puvimedusa.pdfIn PDF document text
    • http://rcsiprojectracker.com/userfiles/files/22303566022.pdfIn PDF document text
    • https://247hvac.ca/fabulous1/uploads/files/57754148507.pdfIn PDF document text
    • http://mediasingrid.com/js/new/fckeditor/userfiles/file/83177221005.pdfIn PDF document text
    • http://versobrokers.eu/userfiles/files/24190158336.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+factory+reset+android+head+unitPDF 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_off0000eba0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBA0 17176 bytes
SHA-256: 6baadde6a84fb9a1dd479d665eef1db551a65307540fe98c11d8be63a2eb7697
font_01_sfnt_off000118b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118B3 10820 bytes
SHA-256: 3a05b750b06da4403193fc8885a927ef05daea1600575db62c73344468675509
font_02_sfnt_off000131af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131AF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1