Malicious PDF — malware analysis report

Static analysis result for SHA-256 d284b67540c30995…

MALICIOUS

PDF

83.2 KB Created: 2021-10-21 09:55:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 15651e04b295e2344fc8fbf674030f0c SHA-1: e13595537873cf03f0d0e98fcad4d74a8a48a4d8 SHA-256: d284b67540c30995a116a56839c10f55decb356f3c138350c1adff196d6bf965
156 Risk Score

Malware Insights

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

The PDF contains a large number of external URIs and link farm heuristics, indicating a deliberate attempt to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The embedded URLs point to various PDF files hosted on potentially compromised CMS uploads, reinforcing the link farm and distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://tetobox-budapest.hu/uploads/files/30929703060.pdf In PDF document text
    • https://aksusu.com/upload/files/xubifuwi.pdfIn PDF document text
    • http://budapesticukraszdak.hu/userfiles/files/dewigoxigabaseje.pdfIn PDF document text
    • http://svb-volleyball.de/userfiles/file/pizusij.pdfIn PDF document text
    • http://surausa.com/uploads/files/46871068819.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1614ec0b18a407---44524441357.pdfIn PDF document text
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/a054c89744f860b5baa7780c18284fc2/9519484568.pdfIn PDF document text
    • http://cichanski.com/Upload/file/67249909525.pdfIn PDF document text
    • https://eastoncn.housemember.com/uploads/files/25361760166.pdfIn PDF document text
    • https://franchisefarm.franchiseharbor.com/files/files/69989206167.pdfIn PDF document text
    • http://urparitet.ru/admin/ckfinder/userfiles/files/wikikubakofet.pdfIn PDF document text
    • http://www.urbanwaterways.info/files/14293589810.pdfIn PDF document text
    • https://autoprofi.ua/userfiles/file/97613137790.pdfIn PDF document text
    • http://ngocminhcnc.com/demo_thietbimay_24_7/upload/files/68865249382.pdfIn PDF document text
    • https://nullemont.fr/nullemont/ckfinder/userfiles/files/pelurujowebuved.pdfIn PDF document text
    • http://cuboni.com/uploadfile/hong202109240102061518.pdfIn PDF document text
    • http://xn--12cm8caae5d9a0a0a1dxk6dd.com/user_img/files/81750606401.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1615af8d6f34ad---83523908799.pdfIn PDF document text
    • http://avtokapriz42.ru/userfiles/file/97283819387.pdfIn PDF document text
    • https://mimpishiodua.com/contents/files/puxufeduseb.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/16145e0cbbbc5f---45607904667.pdfIn PDF document text
    • https://sieuthimaycafe.vn/uploads/file/10775195049.pdfIn PDF document text
    • http://straub-online.ch/userfiles/files/15794019918.pdfIn PDF document text
    • http://feedproxy.google.com/~r/MbOu/~3/4dZi1sgP-vI/uplcv?utm_term=bank+manager+exam+question+paperPDF 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_off0000e0ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0AC 11044 bytes
SHA-256: 3c83bdfc04ddeace324d5d35b65e02a3c063fc4058929cb8cab31a44fa3dffa9
font_01_sfnt_off0000fa1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA1A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001122c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1122C 17220 bytes
SHA-256: cda0a1fd558c54f2a94bf51959471d457b9dffcfbf68706fc1d2efd52be91d1f