Malicious PDF — malware analysis report

Static analysis result for SHA-256 28bed099bfa264d2…

MALICIOUS

PDF

81.7 KB Created: 2021-09-05 06:29:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 33ed01b775cabb6974dae53620031271 SHA-1: 8536081c9922a3e23b2e70a2b346f9b506da1977 SHA-256: 28bed099bfa264d21158689a58c0c1072638c23e0192b40069e17866dd1d033f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains multiple heuristics indicating it is a link farm hosted on compromised CMS uploads. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were directly extracted, the presence of numerous links to potentially compromised sites points towards a phishing or malware distribution scheme.

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.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a7a69179abd---43783453464.pdf In PDF document text
    • http://fine-cottage.ru/userfiles/file/xonod.pdfIn PDF document text
    • http://gorsilawfirm.com/userfiles/file/4068451413.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/160707cf87d3e6---fupewatilezixabasefomikoj.pdfIn PDF document text
    • http://odontoflash.eu/userfiles/files/zezadu.pdfIn PDF document text
    • https://thietbivesinhanhhuy.com/asset/files/pezopovuxuvi.pdfIn PDF document text
    • http://netflor.pl/upload/File/89365175731.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608332102eb67---xeledoviwozigaz.pdfIn PDF document text
    • http://baldonimarcostudio.eu/userfiles/files/46276638656.pdfIn PDF document text
    • https://binarbaidequipment.com/public_html/userfiles/file/30194986149.pdfIn PDF document text
    • http://geredekombiservisi.com/userfiles/file/63717799844.pdfIn PDF document text
    • https://cgeminfos.ma/upload/file/12820865813.pdfIn PDF document text
    • https://babetravelling.com/ckfinder/userfiles2/files/tewigegojetudarenarajage.pdfIn PDF document text
    • https://www.lavishlook.se/wp-content/plugins/super-forms/uploads/php/files/f31d91714726c6ca80bf6c53efd70f72/monoweridobarogogali.pdfIn PDF document text
    • https://akproauto.com/nbloom/fckuploads/file/zovugusotawuduvepo.pdfIn PDF document text
    • https://zegaoyun.com/calisma2/files/uploads/44870021395.pdfIn PDF document text
    • https://anakmeong.com/contents/files/76640349395.pdfIn PDF document text
    • http://loaamtran.vn/files/usersfiles/files/leworafemiwazu.pdfIn PDF document text
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160977f26a4349---62574065177.pdfIn PDF document text
    • http://uceng.net/_UploadFile/Images/file/81240137159.pdfIn PDF document text
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/6c4dd7f19fe24c577679d49adf962212/nepuremaxeresarawagek.pdfIn PDF document text
    • https://ahreco.com/uploads/news_file/jiboloziwepugosikuga.pdfIn PDF document text
    • http://timandlor.com/userfiles/file/49989956556.pdfIn PDF document text
    • http://vekosgroup.ru/userfiles/file/15775238558.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=correction+brevet+fran%C3%A7ais+2018+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_off0000d21b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD21B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ea32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA32 11504 bytes
SHA-256: 9308c8aa38e5ce7bc471c70dbbaf991dee6f28fcf71e9266f31dd3a7f160336b
font_02_sfnt_off0001052b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1052B 19708 bytes
SHA-256: 59b078c46b1e93cc7900b2eba2e9d13381a7e6a6e652fc37f3d917da792f89a3