Malicious PDF — malware analysis report

Static analysis result for SHA-256 f88f7f48dd44cbed…

MALICIOUS

PDF

68.5 KB Created: 2021-09-30 19:30:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a0378deb0e888b875564e31248bdd241 SHA-1: 6063eda7fc439a63fdc8e1480c642a71b4beda46 SHA-256: f88f7f48dd44cbedda71947d3c1171d5b02cb5deb867ebfca51e2be831de8ece
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to manipulate search engine results or redirect users to potentially malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • 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://hung168.tw/UserFiles/files/wakodipixapazowesuxux.pdf In PDF document text
    • https://gcr.goldcrownresort.com/magazine_files/files/xuwalidewal.pdfIn PDF document text
    • https://tidymoney.com/ckfinder/userfiles/files/98723383268.pdfIn PDF document text
    • http://wksystems.net/HotelEstimator/userfiles/file/13355636227.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614f074468f59---24308650992.pdfIn PDF document text
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/tce9r5h9jp88t2vc4nsvrmd5kd/29902779059.pdfIn PDF document text
    • http://susasoft.com/upload/userfiles/files/riwowabobifuk.pdfIn PDF document text
    • https://gdaniec.com/upload/files/18995918486.pdfIn PDF document text
    • http://elitvorota.ru/f/file/sukapebafojaleba.pdfIn PDF document text
    • http://interroadholland.nl/userfiles/file/32864294668.pdfIn PDF document text
    • https://5uempat.com/contents/files/80016741570.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/1613243f26816e---95903953750.pdfIn PDF document text
    • http://voszveszprem.hu/_user/file/vedozagizib.pdfIn PDF document text
    • http://intimatehotelpattaya.com/image/upload/File/guvibukedowirepobixapeb.pdfIn PDF document text
    • http://ingmarcofaedi.com/userfiles/files/lefofewoperimizuvulosod.pdfIn PDF document text
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/dd604e69cf0e38b8155ae7be178fc9ca/48199603600.pdfIn PDF document text
    • https://alzubidi.com/userfiles/files/nevasitizaxusimod.pdfIn PDF document text
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/430f9e531382103838dd97466eca233c/10874793024.pdfIn PDF document text
    • http://wksystems.net/HotelEstimator/userfiles/file/85480367187.pdfIn PDF document text
    • http://saluteebenesseresas.it/userfiles/files/46167423230.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=korean+movie+free+online+websitePDF 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_off0000ae4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE4E 14948 bytes
SHA-256: 93a466a833cb54743f72b22e1553271a9995aa1335ab05cfebe0d99893524c8a
font_01_sfnt_off0000d3c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3C4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ebdb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBDB 10656 bytes
SHA-256: 366b12fd8f3f3c25e86a739bd376c1536311b475c6d75ddd5baf40495d4fa749