Malicious PDF — malware analysis report

Static analysis result for SHA-256 b31b3e00650b0578…

MALICIOUS

PDF

84.8 KB Created: 2021-08-17 16:50:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 088fb1c6eb0f5b7026b523e97075c863 SHA-1: 84b4c71a834ac2229e326e5232867d6806412ace SHA-256: b31b3e00650b057877e0a6a19eb141084e5897d30f03bbf2178f3dfdde0fb160
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF was flagged by ClamAV as a phishing trojan and ML classifiers indicated high maliciousness. It contains numerous links, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. While no scripts were explicitly extracted, the nature of the links and the PDF structure strongly indicate an attempt to lure users into clicking malicious URLs, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.justgym.co.za/wp-content/plugins/super-forms/uploads/php/files/6pdrcvdmep2qs340bifc3jtqpn/28299142590.pdf In PDF document text
    • http://scoutpate.com/userfiles/file/nekivekonadawonav.pdfIn PDF document text
    • https://www.sesc-am.com.br/Selecao/ckfinder/files/vewisesazomidij.pdfIn PDF document text
    • http://dges.in/userfiles/file/33943753579.pdfIn PDF document text
    • http://aldo-ins.com/userfiles/file/fotepeloduw.pdfIn PDF document text
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/12d0c675c60a2df588c01a566d4ed6c2/mefaxugizuzafeponosuv.pdfIn PDF document text
    • http://diegogenna.it/userfiles/files/8461956510.pdfIn PDF document text
    • https://intrigantka.ru/images/userfiles/file/zigilarujupamene.pdfIn PDF document text
    • https://www.hotelrestaurantmacarena.fr/ckfinder/userfiles/files/dufurumirolid.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9af235de4c---mewawevek.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608124881f0db---tedijovanelolofuka.pdfIn PDF document text
    • https://hoavily.com/uploads/files/zofirakamarewufufavibop.pdfIn PDF document text
    • http://nfraccon.org/userfiles/file/87094372529.pdfIn PDF document text
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b69fcefd39---piruvobumemij.pdfIn PDF document text
    • https://yukkumpulgroup2.com/contents//files/44266122091.pdfIn PDF document text
    • http://emons-verlag.net/testarea/cwsCMSlight/media/files/narogawudokivurodotejel.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/tipukokivoguvegodex.pdfIn PDF document text
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160986c812e49e---46893616817.pdfIn PDF document text
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16090ce7b86653---zimuxora.pdfIn PDF document text
    • http://www.itidharamshala.in/images/uploads/files/virigizurovigopin.pdfIn PDF document text
    • http://aquarium-kochi.com/app/webroot/ckfinder/userfiles/files/21084911009.pdfIn PDF document text
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/7a409b47cc61afcd77a34bc8a31265d8/ligakenulediromafar.pdfIn PDF document text
    • http://runo34.ru/attachments/file/48773320028.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=how+did+the+great+depression+in+germany+lead+to+ww2PDF 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_off0000e52c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE52C 16840 bytes
SHA-256: 9ceed708301b7f7bbe3571624770711b253aac1cfe0b446ec9bd352a91c7d83d
font_01_sfnt_off00011104.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11104 11152 bytes
SHA-256: aff4a3cb7ffb6a6cccc7a28a93477fe998bf38b9727a1803157332553bf15c01
font_02_sfnt_off00012ac1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AC1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1