Malicious PDF — malware analysis report

Static analysis result for SHA-256 f430a891baaea819…

MALICIOUS

PDF

84.7 KB Created: 2021-10-05 15:49:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 8b5fed0f136c6009b1495bc1f03651a8 SHA-1: f508d929525f6589b23ad57dd4ae1b43340ad21a SHA-256: f430a891baaea819ac1df39a78be305904609a90145b165d67030e59459d1ba9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery through these links. The document body is unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

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 http://rdasesores.gestconcursal.com/editor/ckfinder/userfiles/files/bemoloveviveg.pdf In PDF document text
    • http://heorungminhphat.com/luutru/files/97380835583.pdfIn PDF document text
    • http://lawyergz.net/uploadfile/files/nijorexofuvefunit.pdfIn PDF document text
    • https://greenfuturevietnam.com/Upload/files/vutugugibaj.pdfIn PDF document text
    • http://hueide.com/upload/files/nabeb.pdfIn PDF document text
    • http://avandcie-energy.fr/ckfinder/userfiles/files/77416845092.pdfIn PDF document text
    • http://imosa.asia/uploads/files/202109210237279294.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161406e8787dc9---rulawaxeduman.pdfIn PDF document text
    • http://japhina.com/upload/file/setetut.pdfIn PDF document text
    • http://studiolorenzino.eu/userfiles/files/zofegokobis.pdfIn PDF document text
    • https://kermoulin.com/userfiles/file/nomerewizelewetemefer.pdfIn PDF document text
    • http://www.siscbolivia.com/admin/uploaded/fck/file/91293533788.pdfIn PDF document text
    • https://rubfila.in/files/file/63364114881.pdfIn PDF document text
    • https://intersat.lv/files/file/10001248195.pdfIn PDF document text
    • http://kawoka.com/userfiles/file/jizojanubow.pdfIn PDF document text
    • http://mkconline.com/landmark/ckfinder/userfiles/files/78977425402.pdfIn PDF document text
    • http://www.oiseaubleu-promo.fr/userfiles/file/16148388478.pdfIn PDF document text
    • http://mrcookie.tw/upload/editor/file/201818075614.pdfIn PDF document text
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614287fba75d7---kosiselofusera.pdfIn PDF document text
    • http://lesbambousbleus.fr/ckeditor/upload/files/12516378641.pdfIn PDF document text
    • http://tsuiteru66.com/userfiles/file/bipiwajizedebas.pdfIn PDF document text
    • http://inannamsao.com/uploads/files/batiti.pdfIn PDF document text
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/8212ad7c2fb0cb62079a88296dad6cf7/81824625736.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16154524a9d967---jawatir.pdfIn PDF document text
    • http://villa-margherita.biz/userfiles/files/69465595817.pdfIn PDF document text
    • https://kham.vn/userfiles/file/zikazu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=the+emotional+guidance+scalePDF 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_off0000e079.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE079 10780 bytes
SHA-256: 7530d529e7ce536c306cc36400ea2f65fe3760fe7ccd2c4f8f6fd84fd81fc897
font_01_sfnt_off0000f8dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8DD 19940 bytes
SHA-256: a1310023a4d903d09a9263c0b83455c84da1eac7883ff7023c46fbb1e6aa97aa
font_02_sfnt_off00012c9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C9E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1