Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc4df625cd098e4a…

MALICIOUS

PDF

86.2 KB Created: 2021-09-02 12:43:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 671bec52e77eecb01ae86dde6e6621b4 SHA-1: 590b39650aa17809ae70f457d11da5c28e889e74 SHA-256: bc4df625cd098e4a4844318c75894d39190f8524415a3f860bb3909122d59688
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Numerous heuristics indicate the PDF acts as a link farm, directing users to a variety of external websites, many hosted on disposable domains or compromised CMS uploads. The presence of embedded URLs and the PDF's structure suggest it's designed to redirect users to potentially malicious content, such as phishing pages or malware download sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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 https://laborke.ru/uplcv?utm_term=potty+training+chart+pdf PDF link annotation
    • http://chinajnbt.com/images/upload/File/25478397499.pdfIn PDF document text
    • http://vytvarnyobchod.cz/UserFiles/File/zotipozupidevavawu.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160715d357295d---86593819855.pdfIn PDF document text
    • https://aghs.in/ckfinder/userfiles/files/88388508899.pdfIn PDF document text
    • http://duhochoangthanh.com/upload/files/kesorofedimu.pdfIn PDF document text
    • http://worldcar.jp/userfiles/files/dojukasozudufib.pdfIn PDF document text
    • http://frutapacargentina.com/ckfinder/userfiles/files/buzizenibalujowubol.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e322269520---83240567130.pdfIn PDF document text
    • http://jinistudy.com/_UploadFile/Images/file/xexizimulupotizew.pdfIn PDF document text
    • http://prattsofdouds.com/clients/d/d8/d85aab9f4bcbae69c8358f7a9990a0b1/File/29622104324.pdfIn PDF document text
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/cceju1s68l7r7b2bao098jnbe4/91858866147.pdfIn PDF document text
    • http://northcity.rs/slike/files/bomotudakutixeram.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612614b9aedd0---65969627983.pdfIn PDF document text
    • http://pc75.net/upfiles/file/1621584973.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/160c3b2387d9e2---nupisigagadetafuvuz.pdfIn PDF document text
    • http://maximaviajes.com/FCKfiles/file/32645012424.pdfIn PDF document text
    • http://simmsfamilyreunion.com/clients/9/98/98d47f1658d09d39d77ba56043454c9c/File/zirivasen.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098750956c1c---xilonesum.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/27c17bb05c9cf67285e0a6b84f03143f/60082841212.pdfIn PDF document text
    • https://osakadentalcare.com/contents//files/56905749302.pdfIn PDF document text
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/864ac5578189f238085b87ab95a414e7/xawevoka.pdfIn PDF document text
    • https://aduanaldelvalle.com/userfiles/file/39257977257.pdfIn PDF document text
    • https://sssmri.com/ckfinder/userfiles/files/5491593642.pdfIn PDF document text
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/rqn4iu6bptnra9u8dfgl9l72sa/61111885262.pdfIn PDF document text
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae78eec7b22---bugubazow.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4720ca4803---japuladubozek.pdfIn PDF document text
    • 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_off0000ebc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBC7 10668 bytes
SHA-256: 23bd1b17dcf7b6273cb7db81b959845feafbd86d0d327ce2a5b90115c73b8920
font_01_sfnt_off000103f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103F9 18128 bytes
SHA-256: 413ca4f74dc34d7a8ba594afccef0d2ce822b3ca379cc9e8cd5f59e984b7d1f9
font_02_sfnt_off000132ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132EC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1