Malicious PDF — malware analysis report

Static analysis result for SHA-256 e5868f9ab63774c3…

MALICIOUS

PDF

73.8 KB Created: 2021-09-25 06:24:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 74c4f0ea28d939939fd3324508ca433c SHA-1: 3ae91375e6de1aeee8517b2550aef6b3e02e472b SHA-256: e5868f9ab63774c37289b0025c8e1aba2613a6209b3e94ebe87312c037022460
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to external files on various domains. Several heuristics indicate this is a link farm, with some links pointing to compromised CMS upload storage. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution through these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://nawooelcs.com/upload/userfiles/2021/09/files/210917173446.pdf In PDF document text
    • http://patrickstaxi.fr/userfiles/file/luwikunetixewivi.pdfIn PDF document text
    • http://christopherdallo.com/file/32030234852.pdfIn PDF document text
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/508b10fad3a5be6c2019e88a5eb323bf/marirowipukotobosugojexo.pdfIn PDF document text
    • http://www.propper-droppers.nl/files/file/nofekunuwilefavexanobo.pdfIn PDF document text
    • https://dom4m.com/userfiles/files/74225950045.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614aff0d793fa---52180276149.pdfIn PDF document text
    • https://spirit-legend-enterprises.com/webroot/editor-uploads/files/vesedodezowa.pdfIn PDF document text
    • http://electrogalicia.com/electrogalicia/recursos/archivos/66642788364.pdfIn PDF document text
    • https://www.babetravelling.com/ckfinder/userfiles2/files/kawosifuwo.pdfIn PDF document text
    • https://etimes.mn/uploads/files/11501500873.pdfIn PDF document text
    • http://gmei.lt/ckfinder/userfiles/files/rowezalax.pdfIn PDF document text
    • http://atut-biuro.com/uploaded/file/gisasajovef.pdfIn PDF document text
    • http://photopuzzle.net/userData/board/file/rewiwudevibidoworalilazo.pdfIn PDF document text
    • https://dobre-akce.cz/media/files/file/natetenetedexovugi.pdfIn PDF document text
    • https://mimpishio2.net/contents/files/26230778911.pdfIn PDF document text
    • http://twapp.freshkon.com/upload/files/livalupuj.pdfIn PDF document text
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161441425cdfec---zedasoduvow.pdfIn PDF document text
    • https://giant-nano.com/app/webroot/userfiles/files/23225897627.pdfIn PDF document text
    • https://www.emcp-pmce.ca/_includes/ckfinder/userfiles/files/44791817814.pdfIn PDF document text
    • http://dreiseengrundschule.de/files/73143378060.pdfIn PDF document text
    • http://educaholistica.com/resources/img/imagesck/files/45518173637.pdfIn PDF document text
    • http://gourmethousemacau.com/UploadFilesfile///dowevalejerisasozubodu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=marsden+tromba+vector+calculus+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_off0000bb05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB05 10988 bytes
SHA-256: 51857f64b66e4ef24e413006af105edefbc60775b61a0be6ab940f1affbdcf89
font_01_sfnt_off0000d45a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD45A 17664 bytes
SHA-256: 99e703c02de3eb7850683cb7d51ed2ed3aa6a76d96339bded7be345e0794ff07
font_02_sfnt_off00010179.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10179 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1