Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4f75e1fd43bcbf1…

MALICIOUS

PDF

87.2 KB Created: 2021-08-12 02:16:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: d6f229379a3a8d59b5e975ede69fbbc4 SHA-1: 54de420c08a5e08ae04fd3e23420919ee238cceb SHA-256: b4f75e1fd43bcbf145c5d9fb8cfe2386a7f0f3721e91e026aa228dee7d28f4a0
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of embedded URLs, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to potentially harmful sites. No scripts were extracted, but the primary attack pattern appears to be luring users through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://philabc.ru/uplcv?utm_term=differences+between+chemical+weathering+and+mechanical+weathering PDF link annotation
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1610ed14b3d374---bubovewokodezasuromi.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a3e8dd61ca6---navefa.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608345c263e86.pdfIn PDF document text
    • http://orbitsecurity.qa/pro_mvp_tech/uploads/file/45432069257.pdfIn PDF document text
    • http://mixmarketing.vn/upload/fck/file/36145031470.pdfIn PDF document text
    • https://stallion-international.com/userfiles/file/rixagaxofixeparijerudopot.pdfIn PDF document text
    • http://sinhorelli.com/userfiles/file/20474893568.pdfIn PDF document text
    • https://study4student.com/cache/fck_files/file/83139262425.pdfIn PDF document text
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ac42a58389---suziwudujagozogegokaz.pdfIn PDF document text
    • https://xpress2.eu/ckfinder/userfiles/files/tolarunajebewozinot.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/b54efe8e74140534e2de5c4d2d702db1/23842196237.pdfIn PDF document text
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16104e273f3a3f---4228163305.pdfIn PDF document text
    • http://dtcguild.org/clients/80367/File/10251214910.pdfIn PDF document text
    • http://vector-mebel.ru/uploads/files/doninalipimexorotib.pdfIn PDF document text
    • http://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/ba038f6eddcbab77ef7cfa76d96681e0/40157290908.pdfIn PDF document text
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/21dd1c1af6672fc8fec5313a9421481f/94355866020.pdfIn PDF document text
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/15d77eb95a315ba395e0deaf1405224c/woxamepeboxovajavugot.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d5ad251ba58---pilij.pdfIn PDF document text
    • http://sarljarry.fr/userfiles/file/58131919721.pdfIn PDF document text
    • http://szalkasszorutacskok.hu/app/webroot/files/content/files/fepag.pdfIn PDF document text
    • http://liburnia.pl/userfiles/file/33302110728.pdfIn PDF document text
    • http://nuestratierrapremios.com/campannas/file/banil.pdfIn PDF document text
    • http://arcdesantmarti.com/biocop/Images/images-editor/file/rijadegedit.pdfIn PDF document text
    • https://anakmeong.com/contents//files/96572024709.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_off0000f2d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2D0 11028 bytes
SHA-256: b1fb76f50b949de63bae91dc7d8c46da256403ffb41f4c4c3fef07f8caa75ea2
font_01_sfnt_off00010c2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C2C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001243e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1243E 16096 bytes
SHA-256: e2babf919090b5b06b6c05faecc9da44dd9f7bf675acf53294ca8c6c2165d37f