Malicious PDF — malware analysis report

Static analysis result for SHA-256 858d3509ff222e7e…

MALICIOUS

PDF

98.4 KB Created: 2021-07-05 06:59:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 194eeee3299e2e0edc4ef293a6316c03 SHA-1: 13061b1c96cb5511716b4cd7caf89f8c8cbb379b SHA-256: 858d3509ff222e7e7004c4cb1f351e770b145f2daa65a3f1760405ef23226b8e
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, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The presence of multiple unknown URLs associated with formcraft plugin uploads further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

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://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16082e2c22c6c9---45541586997.pdf In PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607911496fa6a---dukijajaberobomilijes.pdfIn PDF document text
    • http://uro-medical.pl/zdjecia/fotki/file/renopofubedikifevoxok.pdfIn PDF document text
    • http://namuvaldymas.lt/userfiles/file/21232272508.pdfIn PDF document text
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/423056187b7637ee3927ddf227602aa0/zokajaxediwu.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607402672fc00---duketejiwuzofesarubu.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16081b30b24fd4---3790618670.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adef42cefb1---55385625729.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/2ehuasqp32ikvl1u6edhs24ef6/54777430847.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/d6b104a6232051b6f3937cc9d83dba5d/9527396295.pdfIn PDF document text
    • https://semsaesp.com/ckfinder/userfiles/files/wupolosimef.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606da492126f7---dabikewogaxapeti.pdfIn PDF document text
    • http://payassistinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074720f147a3---zexikonefixoju.pdfIn PDF document text
    • http://www.abcklima.hu//data/editorfile/topuvaw.pdfIn PDF document text
    • https://amd-export.com/site/upload/file/71161425458.pdfIn PDF document text
    • http://ghibms.com/userfiles/files/datowubovi.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8bebdf3a44---rutiz.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/7nvbhb1tmnlubievk8e9mq9vg6/zorotetovizaboxexa.pdfIn PDF document text
    • http://dirabrealtors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b5699daedb---60071127252.pdfIn PDF document text
    • http://sanitaerprofi.ch/fckeditor/editor/images/file/bixiraxijexiwetowiwaje.pdfIn PDF document text
    • http://tdfinalists.ca/clients/43449/File/30584924203.pdfIn PDF document text
    • https://coluer.ir/documents/file/zuxogetofuf.pdfIn PDF document text
    • http://billedbutikken.dk/articlefiles/file/zijotupogewawufepi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=angry+birds+star+wars+2+unlimited+moneyPDF 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_off000115f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115F4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012e0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E0B 11132 bytes
SHA-256: 3ac0843b49757ad27e1212f5de0861757cb67a32e433c7977d22ff9b292e6152
font_02_sfnt_off000147f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x147F8 21148 bytes
SHA-256: 8765b0286ef772c0c5c7a21a5e26afd2660a1e87650e0606a510dd080be16edd