Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac521d0537444037…

MALICIOUS

PDF

81.5 KB Created: 2021-07-01 22:45:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: c3727ca7fb1121537fe47cbca2936f7b SHA-1: 769a0bf5e0b445f783e1b2d1000caa2cd58db804 SHA-256: ac521d0537444037dd6abc0818d7da3ec5ae451d4e2a33714720cef44d67f528
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains a link farm pointing to numerous distinct hosts, many of which appear to be compromised WordPress sites or disposable hosting. The primary purpose seems to be directing users to malicious content via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/4b0493aadb20091045e8b0590e24c39a/bupapuvelanuvaz.pdf In PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607f4c09aa6cd---zevipepekigufarexo.pdfIn PDF document text
    • https://arredamentigiacobbe.it/file/65729777181.pdfIn PDF document text
    • http://penzion-u-zamku.cz/files/file/8386157245.pdfIn PDF document text
    • https://kogan-photo.ru/wp-content/plugins/super-forms/uploads/php/files/0f3ae94bcf41292ac87ea41877830e62/20762059999.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a310a3ba93f---soxogobiwosorezufero.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/2t4gj5k3qh5ck589ql7gi09tj4/lejexinetitoxofe.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf1975b2378---butoxaxezinukeg.pdfIn PDF document text
    • http://chinazzjx.com/d/files/mubetapoboxanur.pdfIn PDF document text
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/a9d453da11f54f4d82f61745e6dfc955/53660714159.pdfIn PDF document text
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1609de8db320fd---77883818899.pdfIn PDF document text
    • https://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/s3lt1e6t7s4uj34j5igufk6on6/93201468448.pdfIn PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/27a4ada5d5843a17924ecf0a99c69f85/38905153472.pdfIn PDF document text
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/a27899f5f0f8bf3cdbcfae6977cbf67e/lerirowowejozexufale.pdfIn PDF document text
    • https://www.chesapeake-lighting.com/wp-content/plugins/super-forms/uploads/php/files/4826b0ba7e0df54bca83e6f59403d55a/tomageno.pdfIn PDF document text
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/7feca4d62c40dd7b8154514bf53c46d0/fesulenenuluderise.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/bs04j02v9fqro8tgn6uqg8hgv5/33799415389.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/o3r535iniv5c6om8m7olrkfvqi/tirigukulakez.pdfIn PDF document text
    • http://bitite.lv/media/txt/122/file/dogoponiwatobavet.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16096ed3459cdc---35805143609.pdfIn PDF document text
    • https://www.pennlighting.com/wp-content/plugins/super-forms/uploads/php/files/f8671bb0b774077555c0634fa1293106/nakomo.pdfIn PDF document text
    • http://dental-forum.ru/userfiles/file/buwagogupof.pdfIn PDF document text
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cf83c4b776---fipufedokolotaf.pdfIn PDF document text
    • https://gberwanda.com/gbe/useruploads/blogs/files/38646797388.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/lifujabas.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=first+certificate+in+english+1+with+answers+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_off0000c700.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC700 10892 bytes
SHA-256: e272a3b75032949e91f150954c4e09cff3df335c4e1e70f883abd34f198b12f1
font_01_sfnt_off0000e009.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE009 29336 bytes
SHA-256: d200b971e2270a0212f5236df4388867528cb506bdc4f2f3c49b8258932c94f0
font_02_sfnt_off00011e24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E24 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1