Malicious PDF — malware analysis report

Static analysis result for SHA-256 50096fa6b95b83e8…

MALICIOUS

PDF

87.4 KB Created: 2021-06-15 16:50:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: df216c55251e7e8e9cab3afede4e043e SHA-1: 0b2171b5f64d7d723068e5820cf3f0fc1a6b40c7 SHA-256: 50096fa6b95b83e8ad315a00e850f5788c3b29aa12171c40fc991ddb3918982d
156 Risk Score

Malware Insights

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

The PDF document contains numerous embedded URLs pointing to compromised WordPress sites and disposable domains, indicating a link farm designed to lure users to malicious destinations. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, and the document body was heavily obfuscated, limiting further analysis of specific payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://irlanc.ru/uplcv?utm_term=law+of+sines+ambiguous+case+worksheet PDF link annotation
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/gan9tmo4253icd4i37c5th56j2/86953838328.pdfIn PDF document text
    • https://circolodelpistone.ch/userfiles/file/nuxadafawadikibonepeg.pdfIn PDF document text
    • http://essiac.cz/UserFiles/file/87370991132.pdfIn PDF document text
    • https://audit-advisers.com/userfiles/file/64833713572.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076c284521a0---67153963599.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/ed2bed0a66056a0c0cc10ece0cd5c588/68548209043.pdfIn PDF document text
    • http://thongthien.vn/upload/files/nivojuvok.pdfIn PDF document text
    • https://robotics-institute.com/wp-content/plugins/super-forms/uploads/php/files/5pbjkstkedjj6t1lpv54kg38ht/32834132457.pdfIn PDF document text
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160816b530c7fd---73329839486.pdfIn PDF document text
    • http://dawahcity.com/userfiles/file/41188044814.pdfIn PDF document text
    • https://talleresimad.com/images/subidas/files/xadarezanilunumel.pdfIn PDF document text
    • https://ppuhperspektywa.pl/files/edytor/file/lanedu.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160adea5a4bd8a---47514278514.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c8ab3db14f2---belomukupururafilun.pdfIn PDF document text
    • http://app8itebarandgrill.com/admin/images/file/29738510044.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a5b4086d87a---97571294552.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn 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_off00010140.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10140 5500 bytes
SHA-256: 3cb420eaff91c01c1301107353876edff35bd00dce3b98517b2205e286343906
font_01_sfnt_off000113f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113F3 11604 bytes
SHA-256: dc69543f76547e4deb55340b8493d538b52cb45516407a8c13c4bc47de0367a3
font_02_sfnt_off00013b93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B93 16116 bytes
SHA-256: 440b3ede0c25df950aed69164220a8caa44108d54563ae21d99fc1559bff7be8