Malicious PDF — malware analysis report

Static analysis result for SHA-256 39a90fdef4a9b175…

MALICIOUS

PDF

81.6 KB Created: 2021-09-07 00:46:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 09c6de85d41fb820a945f7f4b5e23bb3 SHA-1: cc1c6d4314f9d912b2991a4976c67d568a8bf607 SHA-256: 39a90fdef4a9b175dc39211c3d16e97649e598fe50f0db2863534695a172cf3d
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to websites that appear to be compromised CMS uploads, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent. No scripts were extracted, but the structure and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ecc735e77f---nitubatavexekuxub.pdf In PDF document text
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/a79948b6d18ac37c7ec49a0a04530a57/41435138531.pdfIn PDF document text
    • https://armenia4d.com/contents//files/22498624379.pdfIn PDF document text
    • https://floraplant.gr/FCKeditor/userimages/file/metuzunozanazorabawa.pdfIn PDF document text
    • http://offerseir.com/basefile/offerseircom/files/75282592200.pdfIn PDF document text
    • http://air-ned.com/uploads/files/22134082435.pdfIn PDF document text
    • http://antasboru.com/guvennet/resimlerfiles/jusunag.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160848788b8201---xufejawaniwavevu.pdfIn PDF document text
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/up8knut7i57340itmqjqibat54/61501447266.pdfIn PDF document text
    • http://pr-jam.com/ckfinder/userfiles/files/82047140941.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608f67f7d186a---67985449503.pdfIn PDF document text
    • http://kimhoatra.com/upload/fckimagesfile/97470092177.pdfIn PDF document text
    • http://sosnovgeo.ru/userfiles/file/ragujanexunezitewazoz.pdfIn PDF document text
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160805c9f8bf80---budokurifuzaruvowu.pdfIn PDF document text
    • http://shopsuathientu.com/uploads/userfiles/file/texanarimosirerufosorilak.pdfIn PDF document text
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16084bce5d2910---zekobogusarogodutuk.pdfIn PDF document text
    • https://rsun.pro/admin/ckfinder/userfiles/files/34017666094.pdfIn PDF document text
    • http://lakshimi-kaatsu.com/user_data/packages/default/imgfiles/51617548759.pdfIn PDF document text
    • https://samyenngochoang.com/wp-content/plugins/super-forms/uploads/php/files/mfhce232i5jm9s3de376t50c3s/23402259749.pdfIn PDF document text
    • http://brickchamber.com/ckfinder/userfiles/files/bitiredesaseboremezo.pdfIn PDF document text
    • http://dream-mebel.com/pic/file/45158587632.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/d75636683beee9594feb683ca28f1c66/mumulasobudu.pdfIn PDF document text
    • http://muslimofwestbengal.com/mwb/editor_upload/files/84678605168.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/1bb6fea2f005b6bb41f8592e945d8a95/dajodazin.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=memutar+rotasi+pdfPDF 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_off0000d9fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9FA 10600 bytes
SHA-256: f9b8f6a6d8d531a0197685a7ef0456d8380cd91eee99888681f85ac7c4f2fd91
font_01_sfnt_off0000f233.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF233 17872 bytes
SHA-256: 29e0097a0c72fdad94daf0fbb97feff92f8dffce1907ae4d49926e4e63de5357
font_02_sfnt_off00012098.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12098 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1