Malicious PDF — malware analysis report

Static analysis result for SHA-256 c443aa75df4c41b1…

MALICIOUS

PDF

67.2 KB Created: 2021-09-10 10:21:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: b2b7ada98b785c748b26cd19fcffd801 SHA-1: 66873f207d43688aed6bcd574765d07191b7965e SHA-256: c443aa75df4c41b15c2cc7c3d567d829442856a3a73b5c79a9554f45e49538ea
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and uses an image-based lure. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 2 text block(s), carries a click-outward action, and is only 67 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://medvor.ru/uplcv?utm_term=mafia+3+free+download+for+android PDF link annotation
    • http://security-m.jp/tool/images/file/50444186906.pdfIn PDF document text
    • https://avukatwebsitesi.trakyasoft.com/upload/files/lunij.pdfIn PDF document text
    • http://apsara.ru/userfiles/file/84734193150.pdfIn PDF document text
    • http://sxcec.org/userfiles/file/68727529380.pdfIn PDF document text
    • https://kanalprofi.at/UserFiles/file/28820894120.pdfIn PDF document text
    • https://alquimia.in/admin/fckeditor/editorfile/39704572784.pdfIn PDF document text
    • http://oldstat.ww.tj/img/file/12017817545.pdfIn PDF document text
    • https://glozor.com/userfiles/file/50747873302.pdfIn PDF document text
    • http://www.rupankar.com/fckimages/file/66165661041.pdfIn PDF document text
    • http://cuanhuaabshanquoc.vn/files/zakikipumozot.pdfIn PDF document text
    • https://himalayanthailand.com/image/upload/File/xedabizuluzosuxafavefipo.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/16134eb4249526---44575351158.pdfIn PDF document text
    • http://xn----otbb6ahq3d.xn--p1ai/ckfinder/userfiles/files/18788118468.pdfIn PDF document text
    • http://tiendanatacion.com/noticias/files/bovesekuvem.pdfIn PDF document text
    • https://m-astar.com/UserFiles/files/43026325946.pdfIn PDF document text
    • https://fullgame.hu/uploads/files/wiguwij.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1612ff71263d0e---87103622493.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139e5994690d---vefovetadekafid.pdfIn PDF document text
    • http://www.rupankar.com/fckimages/file/95039539615.pdfIn PDF document text
    • http://twapp.freshkon.com/upload/files/juxaxu.pdfIn PDF document text
    • http://assotechne.eu/userfiles/files/jakoxuzikonuvezuwulesit.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_off0000ac3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAC3E 14184 bytes
SHA-256: e471ce6e0307e980260cfe1d23c57f550da39d3e264fb5413ac8a4a30b30dc32
font_01_sfnt_off0000cfc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFC4 10332 bytes
SHA-256: 126d8d561edec3f478a4d68a76bc0e28f59f9fd596b156fcfd785b2d8d61ff5d
font_02_sfnt_off0000e740.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE740 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1