Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff0028d1701b8224…

MALICIOUS

PDF

70.7 KB Created: 2021-09-22 23:56:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: cda3fa6f6a0482e11010e17f0ac2e7ec SHA-1: db93761beb2c505a76101c5bb9a5738c7eaf521f SHA-256: ff0028d1701b822494c36376011673705f2e1f37f19d60b8bd1677c4b8786c3a
156 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed for malicious redirection. ClamAV detected this file as a phishing trojan, and the ML classifier also flagged it with high confidence. The presence of numerous external URIs and the link farm structure strongly suggest an attempt to lure users to external sites for nefarious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://sccsfz.org/upload/2021-09/velapudijunip.pdf In PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b67a1dafcf---mitutesuwedelebekok.pdfIn PDF document text
    • http://envisystem.com/upload/userfile/files/toxuko.pdfIn PDF document text
    • http://daphongthuyhueminh.com/uploads/image/files/78785959271.pdfIn PDF document text
    • http://studiotecnicomartani.eu/userfiles/files/41517856098.pdfIn PDF document text
    • https://www.fyna.com.au/application/third_party/ckfinder/userfiles/files/53169100143.pdfIn PDF document text
    • http://idrogastermoclima.it/Utentifile/FCKPage/file/nerifezudenulepikowupi.pdfIn PDF document text
    • http://thongthien.vn/upload/files/munenazimomawewix.pdfIn PDF document text
    • http://filipdegreef.be/uploads/files/62139059382.pdfIn PDF document text
    • http://xn----0tbbbfo0f.xn--p1ai/userfiles/file/67855501209.pdfIn PDF document text
    • http://skupka54.ru/upload/m/89463882624.pdfIn PDF document text
    • https://kham.vn/userfiles/file/73305016189.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16140769a4874f---fawuzujedovigik.pdfIn PDF document text
    • http://www.contal-farmer.com/uploads/files/74494267359.pdfIn PDF document text
    • http://yushendesign.com/images_fck/file/1631579728.pdfIn PDF document text
    • https://elmaga.lt/components/com_mijoshop/opencart/image/data/files/rokimurid.pdfIn PDF document text
    • http://xn--b1agjlwjc3g.xn--p1ai/ckfinder/userfiles/files/5667166221.pdfIn PDF document text
    • http://fantacyhandicraft.com/userfiles/file/nusevizonof.pdfIn PDF document text
    • http://m-s-g.ru/userfiles/files/68531490174.pdfIn PDF document text
    • https://agrilaui.com/userfiles/file/78695064728.pdfIn PDF document text
    • http://moscow-vernisage.com/files/files/18477673089.pdfIn PDF document text
    • http://project-lovcen.me/userfiles/file/30715002561.pdfIn PDF document text
    • https://bilbox.es/wp-content/plugins/super-forms/uploads/php/files/b3c9e2e49ebd6a3c70a1b2de2d545373/54304499982.pdfIn PDF document text
    • https://oolong-dining-co.com/webroot/editor-uploads/files/tufunexirabagogoveza.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=fb+lite+apk+new+versionPDF 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_off0000b834.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB834 10604 bytes
SHA-256: 9559c8f85c0bd8a855515f97674848de8448347c11cd8e472b5fe9cf15438d7d
font_01_sfnt_off0000d065.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD065 14592 bytes
SHA-256: 8ed90eb34f6a8da534fa038ab564d649f835cb9d2ead9d1a23b9d9994d701d6b
font_02_sfnt_off0000f531.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF531 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1