Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b893efbd073731d…

MALICIOUS

PDF

82.6 KB Created: 2021-09-17 00:06:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 79b721fdeb9cf60a7a74d69b4874079f SHA-1: 68597847f2b446874dd06d1acdb642d3eeeb69b3 SHA-256: 9b893efbd073731d776e8c4dfce6fe82bfabe8698e47d96799a4fd1723df34e6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm containing numerous external URIs, many hosted on disposable or compromised domains. The presence of embedded URLs and the overall structure suggest a phishing or malware distribution lure, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://oniceh.ru/uplcv?utm_term=social+steps+android PDF link annotation
    • http://henghuitong.com/jingkelun/userfiles/files/20210910080103.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16135092dcbd12---xaposudaluxexixowinabusa.pdfIn PDF document text
    • http://tsraccountants.nl/mailing/images/photo/file/kejesubagezi.pdfIn PDF document text
    • http://www.bluefashion.cz/ckfinder/userfiles/files/wikoxe.pdfIn PDF document text
    • https://www.frontieregypt.com/sites/all/libraries/ckfinder/userfiles/files/38301800849.pdfIn PDF document text
    • http://wsm.hk/images/uploadfiles/file/vixobobezokozovexeribon.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/a5e84f09e5804ded5dc75722741cb1d2/21803843440.pdfIn PDF document text
    • http://origo.ws/userfiles/file/vemikepiniloruwiwikenobeb.pdfIn PDF document text
    • http://e-sportis.com/images/upload/gofawufimuzularameli.pdfIn PDF document text
    • https://bya-ingenieria.com/ckfinder/userfiles/files/filulire.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/161332fbca46a9---rupokosanizadarera.pdfIn PDF document text
    • http://pegastelco.com/pictures/files/5051873592.pdfIn PDF document text
    • http://taxplus.in/images/contentimages/files/dedebawigav.pdfIn PDF document text
    • http://christschoolblr.in/userfiles/file/61564151116.pdfIn PDF document text
    • http://trunglam.vn/uploads/userfiles/file/zapigodofugubuwobewi.pdfIn PDF document text
    • http://elpijisystem.com/file/jenivuvetazoravuvu.pdfIn PDF document text
    • http://honda-vo.com/upload/file/rifigubawenelawogajuj.pdfIn PDF document text
    • https://hotelite.in/userfiles/file/75341648150.pdfIn PDF document text
    • https://ivanamihic.com/files/rupafituxunuxe.pdfIn PDF document text
    • https://network-italia.it/file/sevekujafezaraluxoxate.pdfIn PDF document text
    • https://auto826.com/uploads/files/33491042359.pdfIn PDF document text
    • https://pacie.vn/web/uploads/files/29197011241.pdfIn PDF document text
    • https://alkirbilaw.com/userfiles/files/29413898397.pdfIn PDF document text
    • 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_off0000df9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF9B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f7b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7B2 10580 bytes
SHA-256: ed9f8de697bc9e60244e0c559f0059d1fe31d4eba14132ecb96e69da5ee3098b
font_02_sfnt_off00010fe6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FE6 17444 bytes
SHA-256: 4af77babe1c8fb652b11a7002bcb0ea48a4ed3c64fa614ef43d1b0b3d797af45