Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b63519f0b37faf1…

MALICIOUS

PDF

69.3 KB Created: 2021-09-10 21:44:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 4da3f682ee4307ce37772d491dcc85b1 SHA-1: 1f971380334be6a99541832794dbcaf952050ef3 SHA-256: 8b63519f0b37faf18e2d30017d68698acc6837140b23af6e18d11e57ba0f40b5
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on disposable domains or compromised CMS uploads, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6870

Heuristics 5

  • 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
  • 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://archism.ru/uplcv?utm_term=android+sending+pictures PDF link annotation
    • http://kolesnikov.pro/ckfinder/userfiles/files/zeladefifumuk.pdfIn PDF document text
    • http://sandsflooring.co.uk/ckfinder/userfiles/files/jekutatukuvosexis.pdfIn PDF document text
    • http://whitedwarf.ru/public/images/ckfinder/files/67286737066.pdfIn PDF document text
    • https://siliconautomation.com/userfiles/file/zizogivesonelibowulonus.pdfIn PDF document text
    • http://hotel-ambassador-nice.com/upload/files/soraweg.pdfIn PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/c33b4c30726c53d728d7fedb158bc661/10251254732.pdfIn PDF document text
    • https://ladulceseguros.ar/noticias/fckeditor/file/gobevafaduvajigezuron.pdfIn PDF document text
    • http://budka39.ru/files/fudijepim.pdfIn PDF document text
    • http://papinchess.ru/userfiles/file/7982437781.pdfIn PDF document text
    • http://www.contal-farmer.com/uploads/files/74494267359.pdfIn PDF document text
    • https://senfina.top/uploads/files/41359756433.pdfIn PDF document text
    • http://placc.info/up_image/17575309721.pdfIn PDF document text
    • https://tl-systems.hu/files/files/dojeno.pdfIn PDF document text
    • http://www.lbf-cosmetics.com/website/wp-content/plugins/formcraft/file-upload/server/content/files/16137ccc343f1e---nekufizute.pdfIn PDF document text
    • https://biomedchita.ru/imeg_master/file/98088755330.pdfIn PDF document text
    • http://babijie.com/upload_fck/file/2021-9-10/20210910090548932286.pdfIn PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133b7f37d4e5---gulomepubogapinav.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/161336d2d81167---rijarozebebokibofawome.pdfIn PDF document text
    • https://auditorescr.com/ckfinder/userfiles/files/28512065291.pdfIn PDF document text
    • https://aneri12.cz/res/file/78215349453.pdfIn PDF document text
    • http://hongdanhaudio.com/luutru/files/66475098435.pdfIn PDF document text
    • http://daisytalavera.com/userfiles/files/lomebolisivekob.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f116239c78---72357222615.pdfIn PDF document text
    • http://simonkuehner.de/gfx/userfiles/files/7111742374.pdfIn PDF document text
    • https://swagath.co/new/ckfinder/userfiles/files/82066883863.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e68d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE68D 10560 bytes
SHA-256: dc5d2dd0931961ef59c0d7eca660b0b552601a221cad19205780bbb335f882ce
font_01_sfnt_off0000fe96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE96 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1