Malicious PDF — malware analysis report

Static analysis result for SHA-256 68c667e0a204213d…

MALICIOUS

PDF

79.5 KB Created: 2021-09-20 00:52:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 51ffb8c5afeaef7b162d9fd2090f6bcc SHA-1: ac1971f0d861a7088a0471f00bf1a719816c48c0 SHA-256: 68c667e0a204213d9bb2df3987907a1a2bfcca4b1684493f5d48867380038d14
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to compromised websites, suggesting it's used as a link farm to redirect users to malicious content. The PDF structure and embedded URLs point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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 https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/5dg50pcpgn4ilbrrjhmloisn7b/xerozedikunaradi.pdf In PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/161409e76337b3---6761331595.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147a851bec28---14693122043.pdfIn PDF document text
    • http://nacyc.jp/Upload/file/19746171921.pdfIn PDF document text
    • https://yuanfuconstruction.com/ckfinder/upload/files/vinilunit.pdfIn PDF document text
    • http://rfaaa.com/UploadFile/file/20210914162053247.pdfIn PDF document text
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614449994c888---sizusono.pdfIn PDF document text
    • https://panoramabyty.cz/content/73833653694.pdfIn PDF document text
    • http://sherwoodchambergolf.com/ckfinder/userfiles/files/88935669578.pdfIn PDF document text
    • https://taxfirma.com/userfiles/file/zanokeletiriwofupinanupo.pdfIn PDF document text
    • http://sksound.com/userfiles/file/34043857455.pdfIn PDF document text
    • https://designmaster.in/scgtest/eec-new/codelibrary/ckeditor/ckfinder/userfiles/files/bojesowug.pdfIn PDF document text
    • http://ltmetal.com/userfiles/files/zotikufevagozevoxofewum.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/16133b356c9b11---75384657665.pdfIn PDF document text
    • http://www.ettermanenterprises.com/ckfinder/userfiles/files/73938113733.pdfIn PDF document text
    • http://coutleelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/23324800922.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/676499267.pdfIn PDF document text
    • https://almoheetmanpower.com/public_html/userfiles/file/konurilazitijigifop.pdfIn PDF document text
    • https://vsevolozhsk.mebel18.com/uploads/files/kosexumake.pdfIn PDF document text
    • https://cs168.tw/upfiles/editor/files/88917616265.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=square+root+of+26+in+radical+formPDF 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_off0000cf71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF71 18508 bytes
SHA-256: bded9495cad82ed7733a694067c6f6ab7cd4cb9101a39189f6090de2de560adb
font_01_sfnt_off0000ff25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF25 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001173c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1173C 11076 bytes
SHA-256: b4f87aea8dd309d6b6bb96b939bf8897c155a79823be1428563718e26203e3e3