Malicious PDF — malware analysis report

Static analysis result for SHA-256 388b77e04eb56216…

MALICIOUS

PDF

79.9 KB Created: 2021-09-14 09:47:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 1de09552e12b845937459f824e0957ea SHA-1: f381c8715f866db51cf846a2cb88f7ea6a74e05c SHA-256: 388b77e04eb562164e869708e4ebd7f42d7460674e949c44ed121263a5df16fe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or malware distribution attempt. It contains numerous links, many pointing to compromised CMS upload directories, suggesting it functions as a link farm to redirect users to malicious sites. No scripts were extracted, but the presence of external URIs and the link farm structure strongly suggest an intent to lead users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://maxgear.cz/webpagebuilder/ckfinder/userfiles/files/bidunokepuzokaxobeje.pdf In PDF document text
    • http://accessibilite-salle-eau.com/ckfinder/userfiles/files/kegawekokimo.pdfIn PDF document text
    • http://drivescuolaguida.it/userfiles/files/60369689197.pdfIn PDF document text
    • http://orosweb.hu/ckfinder/userfiles/files/78511491977.pdfIn PDF document text
    • http://galaxyjewel.cn/uploadfile/files/savejibutesobotatavat.pdfIn PDF document text
    • https://cs-nippon-cp.com/mailmagazine/upload/files/xomosojasulefotugukufeko.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/1094e631cfc922f6ec4767c2e28e19f1/nedumoxoni.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131b7aa01014---28333430843.pdfIn PDF document text
    • http://thesciencenetwork.org/uploads/files/92834126803.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/16130077626bd5---10767009741.pdfIn PDF document text
    • http://radio6deenero.com/uploaded/files/95120684896.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/amg3rhp07hnpm6utc076itjh35/19150424066.pdfIn PDF document text
    • http://www.aunay-sous-auneau.fr/ckfinder/userfiles/files/57367406290.pdfIn PDF document text
    • https://accu-split.com/userfiles/files/kisexiziwa.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/92516412920.pdfIn PDF document text
    • http://itcbeautytrainingschool.com/userfiles/file/jozabazufutopab.pdfIn PDF document text
    • http://kasintorn.com/images/upload/files/7831160789.pdfIn PDF document text
    • https://lotteppta.net/beta/assets/file/sonedibixibajuxerogimizi.pdfIn PDF document text
    • http://stellarvvv.ru/ckfinder/userfiles/files/3934369205.pdfIn PDF document text
    • http://fisioterapiasuzzara.it/userfiles/files/13877573049.pdfIn PDF document text
    • http://ccadl.com/files/20210910190428.pdfIn PDF document text
    • https://www.channeloflove.com/ckfinder/userfiles/files/72075214947.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/2cbf393535ba00b3fc7c4443fa2bebf9/mezogakile.pdfIn PDF document text
    • http://struttur-arch.it/userfiles/files/mobavutimuzabipazonux.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=the+guide+to+getting+it+on+free+downloadPDF 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_off0000d437.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD437 17208 bytes
SHA-256: 906a370d206a31c7469f6387e9416828e456a03662b4c1ce9f41b441750f5a54
font_01_sfnt_off00010158.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10158 10612 bytes
SHA-256: b581961962913082521f66cfd942933cdf4a9b7067d338c4c114fe85db98a16f
font_02_sfnt_off00011962.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11962 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1