Malicious PDF — malware analysis report

Static analysis result for SHA-256 85e75e5c2b60d413…

MALICIOUS

PDF

82.0 KB Created: 2021-09-22 14:38:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e06f228818a8b530d48e883c81d9c828 SHA-1: dab119380dd95e900b6001026187800f2f0b71fa SHA-256: 85e75e5c2b60d413491078547fd68568c6ad47795b3d291fef108e37e42263b9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous external links, with several heuristics indicating it functions as a link farm. Some of these links point to compromised CMS uploads, suggesting a potential distribution point for malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://ornito-silesia.eu/userfiles/file/wufozibedisakimikusawerel.pdf In PDF document text
    • http://webbuilders.com/files/file/93172011455.pdfIn PDF document text
    • http://clainvest.pl/userfiles/file/petexo.pdfIn PDF document text
    • http://alliance-ic.ru/uploads/file/jufakolutusujotu.pdfIn PDF document text
    • http://3colorjazz.com/fckeditor/userfiles/image/xenenaxuxulududomulem.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/nuxofeto.pdfIn PDF document text
    • https://ferdavagnar.is/images/fck/file/83706775726.pdfIn PDF document text
    • https://efficimm.fr/userfiles/files/52355379681.pdfIn PDF document text
    • http://ydyb.com/filespath/files/20210908025457.pdfIn PDF document text
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/6ddc1eca40a2468047753bde6d4f06cc/25903133843.pdfIn PDF document text
    • http://tmkb.org.tr/ckfinder/userfiles/files/jixuwasizuketurumirepi.pdfIn PDF document text
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/6330573cdfbb78d07142ad3bebe170f5/92481942933.pdfIn PDF document text
    • https://ags-car.com/upload/files/99845911514.pdfIn PDF document text
    • http://xn----dtbsgbucafmmaf.xn--p1ai/servimages/editor/files/15295897975.pdfIn PDF document text
    • http://skrabl.pl/www/rpbd/fck/file/77465841961.pdfIn PDF document text
    • http://autolavaggiocraparotta.it/userfiles/files/rezubajekew.pdfIn PDF document text
    • http://worshipedia.net/sites/default/files/file/sikarutagixebunupixevowef.pdfIn PDF document text
    • https://baoholaodong24.com/userfiles/file/91066053763.pdfIn PDF document text
    • https://minhvuongthuphap.com/upload/ck/files/mobobifezurukenoso.pdfIn PDF document text
    • http://moiarchitekci.pl/pliki/file/44870416366.pdfIn PDF document text
    • http://biosafety.biz/ckfinder/userfiles/files/jovabovakajibaturor.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16130506c25b10---69992052414.pdfIn PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1613432c6d3d81---kufimanepo.pdfIn PDF document text
    • http://plkorea77.com/ckupload/files/tadixaladalilerifotuxos.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=hello+kitty+lunchbox+mod+apkPDF 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_off0000dbfc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBFC 17676 bytes
SHA-256: d2b7e521cbd1a9022d581373809ef80ab817bd3bd6934f5ca311aea51eaabd51
font_01_sfnt_off0001096d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1096D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012184.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12184 11052 bytes
SHA-256: 0dab872fb4e4e36efab55a582babea3f5033be1d5fe6dd0095ea80f0d9a0917b