Malicious PDF — malware analysis report

Static analysis result for SHA-256 38c5eeee021c57cf…

MALICIOUS

PDF

83.1 KB Created: 2021-09-12 12:45:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 4f638e199fb3b663139bc7ec8eef7904 SHA-1: ae4f7df6637f1283f1c8bc2efc9a2609d67a9197 SHA-256: 38c5eeee021c57cfbb7b8580a46245fa4f85a5ac1a6cb3569e8f9ff416f3df40
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised websites and disposable hosting, characteristic of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO abuse. The document body is heavily obfuscated and does not provide clear textual lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/161328432b6334---vegadapazebewoxekodedaxuv.pdf In PDF document text
    • http://studiotecnicomaglio.it/userfiles/files/77617439325.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/67384018359.pdfIn PDF document text
    • http://windowsplusllc.com/ckfinder/userfiles/files/49040048840.pdfIn PDF document text
    • http://galenbio.com/images/upload/file/tuxafatutosisamikod.pdfIn PDF document text
    • http://dayuntang.com/assets/uploads/ckedit/files/20210905183633.pdfIn PDF document text
    • http://assotechne.eu/userfiles/files/jarise.pdfIn PDF document text
    • https://avigailpekelman.com/sites/default/files/file/bedosere.pdfIn PDF document text
    • http://studioferrato.it/userfiles/files/pozorat.pdfIn PDF document text
    • https://www.abandassociates.com/ckfinder/userfiles/files/xunawota.pdfIn PDF document text
    • https://www.ewdel.cz/ckfinder/userfiles/files/36911374426.pdfIn PDF document text
    • http://onlinetradeshow.ir/uploads/files/11127129449.pdfIn PDF document text
    • http://interstroy96.ru/uploads/files/72932230418.pdfIn PDF document text
    • http://waxiangyuan.com/upload_fck/file/2021-9-12/20210912000314911485.pdfIn PDF document text
    • http://lawfirm.vn/MINH/user_files/file/rilolebepebapabiribegojim.pdfIn PDF document text
    • http://reliancefla.com/admin/images/file/worer.pdfIn PDF document text
    • http://capitaldanceacademy.com/userfiles/files/fireliromumemukesekoxi.pdfIn PDF document text
    • http://unitez.net/images/newtech/files/11392287336.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/jamejukopipajepobob.pdfIn PDF document text
    • http://sarkar.ie/userfiles/file/86967924125.pdfIn PDF document text
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/161375d493f5f7---tozulezebide.pdfIn PDF document text
    • http://change4best.ru/upload/file/gafelul.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1613011a68a09e---34443997593.pdfIn PDF document text
    • https://ebooksweb.net/files/file/679744002.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613ad66d634be---mugotomodowuwig.pdfIn PDF document text
    • http://radio-salsa.com/php/rs/filesupload/file/pupun.pdfIn PDF document text
    • https://cbdc.co/uploads/ckfinder/userfiles/files/jogotirujavoka.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=how+to+find+android+devicePDF 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_off0000e0d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0D9 10396 bytes
SHA-256: d607e383d1579b4b4c92e99115c70d949a1bf22751a9a6f87eb05cb402c35d37
font_01_sfnt_off0000f87b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF87B 17764 bytes
SHA-256: bc83a3ecd078d972b8ffe7940300352c28f1ec5e7a7cee95a1b3f39c39aa4380
font_02_sfnt_off000126c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126C8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1