Malicious PDF — malware analysis report

Static analysis result for SHA-256 c39e5491f2635e39…

MALICIOUS

PDF

84.0 KB Created: 2021-09-07 20:45:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: c1332919b0dedff53742e5b3296050ac SHA-1: d9ddf919e0e6189142bd9a9a7e29cda096328a52 SHA-256: c39e5491f2635e397966ccc25359b8adfb75238c381cc633b75110faffe1314d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm with numerous URLs pointing to compromised CMS upload directories, a common technique for hosting malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and embedded URLs suggest the document's purpose is to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606d40bdab7f3---76868140788.pdf In PDF document text
    • https://almuhja.ps/ckfinder/userfiles/files/guvexovowumebixusux.pdfIn PDF document text
    • http://luatsugiadinhviet.com/upload/ck/files/fupoxuz.pdfIn PDF document text
    • http://bidmitt.com/img/files/file/wabokuxokiw.pdfIn PDF document text
    • http://canavesiobruno-architetti.it/userfiles/files/25470569083.pdfIn PDF document text
    • http://alnadaoil.com/userfiles/file/44326255142.pdfIn PDF document text
    • http://tbvshungviet.com/upload/files/1404782110.pdfIn PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/160cae8bc94b6f---86225368251.pdfIn PDF document text
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/80316f8387c9b1c497bc2e9188356dbf/86482769997.pdfIn PDF document text
    • http://ieeepes-thailand.org/app/webroot/files/files/sexuteliwajenawolunapef.pdfIn PDF document text
    • https://www.webplease.it/wp-content/plugins/super-forms/uploads/php/files/vtou6fhpq2ic4in7j7uspfelfk/30798029094.pdfIn PDF document text
    • https://doublehaircenter.com/upload/ckfinder/files/tixasusibetazoka.pdfIn PDF document text
    • http://pension-erlkoenig.de/img/editor/file/ziforuloxoxipe.pdfIn PDF document text
    • https://unchiulmihai.ro/files/fckeditor/file/77969869771.pdfIn PDF document text
    • http://kfnmdg.com/upfolder/e/files/20210625101625.pdfIn PDF document text
    • https://unitjaya.com/contents//files/85981678578.pdfIn PDF document text
    • http://kmsenior.org/file/files/xavutudisadewenukinalo.pdfIn PDF document text
    • https://goodline.by/userfiles/file/49195031972.pdfIn PDF document text
    • http://buydecor.ru/uploads/files/tesibiz.pdfIn PDF document text
    • http://franklcalabreseattorney.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nazodolafogexolivikezekuk.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=krishnamurti+biography+pupul+jayakar+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_off0000d954.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD954 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f166.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF166 20496 bytes
SHA-256: 84cad658b8a7b21e1087620bf3dd02e884457a5b401bd95698808063a3408644
font_02_sfnt_off00012686.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12686 11380 bytes
SHA-256: b06af1370a7564155b7754eba99733f606a11f295e4c8f7fa2b177308331d8cd