Malicious PDF — malware analysis report

Static analysis result for SHA-256 b919b19ee2dd13f1…

MALICIOUS

PDF

79.5 KB Created: 2021-09-23 13:50:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a63a4322bd882d0290071ce95d20f38c SHA-1: c46b64c46bd2349867f88bb57d8e8b5dd7de9b3a SHA-256: b919b19ee2dd13f13cb23475a9c02a31c8c9362e2e0a72c653b6e3e9e88ee90f
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to multiple websites, many of which are hosted on compromised WordPress upload storage. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The document body is unreadable, but the heuristics and URLs suggest a tactic of using a seemingly innocuous PDF to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137764a410a5---waronusujel.pdf In PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bc4424630d---40272840351.pdfIn PDF document text
    • http://imreelectric.sk/uploads/file/30562598854.pdfIn PDF document text
    • http://energo-winstal.pl/userfiles/file/69235542352.pdfIn PDF document text
    • http://fongyoskert.hu/userfiles/files/17871067158.pdfIn PDF document text
    • http://hstechno.com/userData/ebizro_board/file/wiwawut.pdfIn PDF document text
    • http://www.bongbansaigon.com/uploads/files/mixafusubiwero.pdfIn PDF document text
    • http://sva-jeanroze.com/xmedia/file/5777986455.pdfIn PDF document text
    • http://lexen.ca/userfiles/files/14016132971.pdfIn PDF document text
    • http://architettosirocco.it/userfiles/files/kupax.pdfIn PDF document text
    • http://spreewaldatelier.de/img/editor/file/xifopa.pdfIn PDF document text
    • https://radekslodkiewicz.pl/files/file/74818424643.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f5cb14905b---jufimudimowodovuderezito.pdfIn PDF document text
    • https://karolinanowak.com/userfiles/file/jelijuzanutapim.pdfIn PDF document text
    • http://lustigersteirer.at/userfiles/file/wakoso.pdfIn PDF document text
    • https://sindicav.com.br/ckeditor/ckfinder/userfiles/files/pejuxosirob.pdfIn PDF document text
    • http://gevenschoenen.nl/ckfinder/userfiles/files/daraditozimakebe.pdfIn PDF document text
    • https://smartmedia.ro/app/webroot/files/userfiles/files/xajepamamorelufuxerosum.pdfIn PDF document text
    • http://glamour-nsk.ru/ckfinder/userfiles/files/xedejumuwepumiraf.pdfIn PDF document text
    • http://nusratali.com/userfiles/files/9616163770.pdfIn PDF document text
    • https://thuhuonglacquer.com/uploads/news_file/gepiguzavovanatumiz.pdfIn PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16148cb255c559---taloroxolununajir.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=mx+player+movies+onlinePDF 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_off0000d451.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD451 10592 bytes
SHA-256: d290531135140341df93409a3d86edcb30315778ea869a72ce2597c9e4ca0975
font_01_sfnt_off0000ec82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC82 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010494.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10494 17204 bytes
SHA-256: d08e671c575e8abb8d344a7a986e4da675c3a21fbf397c7b02464c79bbcdb10e