Malicious PDF — malware analysis report

Static analysis result for SHA-256 df493b335ad7ba14…

MALICIOUS

PDF

88.1 KB Created: 2021-09-17 20:34:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a34500fd12d4440eeb2519e77fb3fa3b SHA-1: c00a73759482fa39f9a09da1b3202dd44bfaf8e3 SHA-256: df493b335ad7ba14ec3872b29c4e557bfdb7e46dd1631d18c37c0783d8b97594
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous external links, many pointing to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users to potentially malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the link farm heuristic and URL analysis.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://cardolf.ro/files/21614116978.pdf
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/f79efc2ea89275911fc7f795761d5773/nebuxopuzoneva.pdf
    • https://zlataraburmevuckovic.com/files/25163767382.pdf
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/2211a59f1667f50a61816f36783c050e/jukazisapisuwejomamesimog.pdf
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/vtldm70b4sjagf7d8qrr9mhjge/disalalejalupaxuro.pdf
    • http://wordtmann.beckbauer.eu/ckfinder/userfiles/files/66689444409.pdf
    • http://www.lifestaralberta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f9f5526634---firarezapelogevad.pdf
    • https://artesapanaderia.xyz/aym_image/files/tewijuzive.pdf
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613886f196179---45483726011.pdf
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/161326a81b7f0a---xesuguzoxajujavugis.pdf
    • https://oriental-kitchens.com/userfiles/files/93639020793.pdf
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161300bbb58326---bokixanix.pdf
    • http://designpavelzapletal.cz/files/file/fudebujosijo.pdf
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/161325c45e7fbb---19079444413.pdf
    • http://jenan.com/ckfinder/userfiles/files/gonuzozoletaditisaweku.pdf
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/161303e2acfe26---49881173529.pdf
    • https://ontech.vn/images/ckeditor/files/94844757521.pdf
    • http://itkaufmann.com/images/fckimages/file/dimokijabozipunesut.pdf
    • https://kozlovka.mebel18.com/uploads/files/1566847392.pdf
    • https://optical-axis.com/uploads/files/202109060156494769.pdf
    • http://www.americaninvest.net/upls/files/10279909242.pdf
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/5cri5k94ts03tvietn17880r3q/patut.pdf
    • http://yummyschool.com/_UploadFile/Images/file/24230067746.pdf
    • http://eventclub.pl/userfiles/file/87241321564.pdf
    • https://www.grdr.org/paidel/ckfinder/userfiles/files/voxudijuxetegopogalafuvo.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=best+android+os+for+pubg+mobile
    • https://cakamuzejs.riga.lv/ckfinder/userfiles/files/labiwilulamexudeb.pdf
    • 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_off0000f268.bin
46f13d855bb249e408e6ed3fbb1dc113b1033029975b961790ad09aa5ae9da64
pdf-font-stream PDF embedded font (sfnt) at offset 0xF268 17856 bytes
font_01_sfnt_off00012127.bin
50dbac41d1729c28369d6edc80dfa565717b4b4f06bff369182610553f954720
pdf-font-stream PDF embedded font (sfnt) at offset 0x12127 11132 bytes
font_02_sfnt_off00013ab9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13AB9 16792 bytes