Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f21f021a32b6444…

MALICIOUS

PDF

87.7 KB Created: 2021-07-30 22:52:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: a232a22ed84b54303e02e1b6594c0a4e SHA-1: 1bd0e48d6382461516e5733877f745825614203e SHA-256: 4f21f021a32b64444ecd617e9d5973faf847ab885737b2f9841df9b143f20584
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 WordPress upload directories and disposable hosting domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/b1f915f7918d4d2380818b0eb4c30419/51998511784.pdf In PDF document text
    • http://infunplastic.com/d/files/21891907801.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/16071debbd8f0d---basepoku.pdfIn PDF document text
    • http://compsult.net/userfiles/file/27098027136.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/ovjv0s8o5o9p0gp8lpp1in1vq2/bokegagu.pdfIn PDF document text
    • https://vanphongphampmc.com/upload/files/selawejiduvanokopituxa.pdfIn PDF document text
    • http://staractivecollection.com/resimler/site/files/gabegi.pdfIn PDF document text
    • https://www.straightmyteeth.com/wp-content/plugins/super-forms/uploads/php/files/df226abe6e9bd39c65a92ab0615cdc7a/dagabebibada.pdfIn PDF document text
    • https://pjkconstruction.ca/images/file/jakadi.pdfIn PDF document text
    • http://www.deep2001.com/images/library/File/mogasesewejigo.pdfIn PDF document text
    • https://tdfstore.it/file/nugat.pdfIn PDF document text
    • http://neonatal-surgery.ru/userfiles/files/pobigujal.pdfIn PDF document text
    • http://dispensapertutti.com/userfiles/files/82867473920.pdfIn PDF document text
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/0f919a215008789073569ccea9e2e521/78307663476.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160817434f266f---rumitigulorozizu.pdfIn PDF document text
    • http://shadesvalleymounties1969.com/clients/868959/File/kunumikifelevisuw.pdfIn PDF document text
    • https://hse.tw/upload/file/21798269587.pdfIn PDF document text
    • http://funperm.ru/content/file/kafovelasugewoviz.pdfIn PDF document text
    • http://sotel-perm.ru/site/file/5862724963.pdfIn PDF document text
    • http://geredekombiservisi.com/userfiles/file/22972245777.pdfIn PDF document text
    • http://globeksa.com/ckfinder/userfiles/files/85881117068.pdfIn PDF document text
    • http://abnicum.com/files/file/32018124816.pdfIn PDF document text
    • http://tubietelbar.hu/uploadfile/kojol.pdfIn PDF document text
    • http://pattersonandoliphantfamily.com/clients/875492/File/bawugedifapa.pdfIn PDF document text
    • https://markyatirim.com/resimler/files/betipojonezepujutojagub.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=envision+math+2.0+grade+4+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_off0000f0fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0FA 11336 bytes
SHA-256: 2a6b94d9d56b4cc9a9443cb43a5a1bfa9006bce78c02b58f51934c21c5a941f8
font_01_sfnt_off00010b4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B4D 16812 bytes
SHA-256: 3152a986c196afe109e97b5c8074b254ad0d7bda47e5730609231b51df7b42e6
font_02_sfnt_off000136a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136A0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1