Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a51db1a10b6e345…

MALICIOUS

PDF

82.7 KB Created: 2021-03-24 19:17:05 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 96f515043dbfb90247b6aa61307b6889 SHA-1: 50c89f919d8fba49a7e425ce770e543c508f57fb SHA-256: 4a51db1a10b6e3458c14c89df9e90763d7c6d245d7b4e1a2f31907203ab46c86
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://soxebez.ru/award?keyword=9th+class+english+textbook+pdf+2020 PDF link annotation
    • http://buyfastedcircle.xyz/931806638928lmlt.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4391308/normal_60045321b97d6.pdfIn PDF document text
    • https://cdn.sqhk.co/xogudililavo/jhNY5ii/frontline_fury_grand_shooter_descargar.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4477373/normal_5ff5580b43128.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366033/normal_603e22aa47e52.pdfIn PDF document text
    • https://cdn.sqhk.co/nurijodefa/Ip5haR6/draw_signature_in_word_doc.pdfIn PDF document text
    • https://cdn.sqhk.co/gaxazazul/oSjheLH/nepidi.pdfIn PDF document text
    • http://leopolds.space/asuran_tamil_movie_bgmicfsq.pdfIn PDF document text
    • https://cdn.sqhk.co/bokirebi/eWhiugf/adt_pulse_compatible_cameras.pdfIn PDF document text
    • https://cdn.sqhk.co/xakurusuk/lFe6djh/jose_chameleone_mateeka_video.pdfIn PDF document text
    • http://geleostone.online/nikon_dx_lenses_35mmuvj54.pdfIn PDF document text
    • http://titanof-filtr.ru/javascript_array_methods_cheat_sheetjr7ey.pdfIn PDF document text
    • http://help-verification.com/mafia_2_health_bug_fix_crack6j0dj.pdfIn PDF document text
    • https://cdn.sqhk.co/pavoraxebute/yhfvjj8/robert_frost_poems.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/fovezewi/vojozovevupedasarotus.pdfIn PDF document text
    • https://s3.amazonaws.com/budovewesekaz/miponobawididu.pdfIn PDF document text
    • https://s3.amazonaws.com/risisipajole/niwugizinumozu.pdfIn PDF document text
    • https://s3.amazonaws.com/sowewazulejewi/34226395358.pdfIn PDF document text
    • https://03aaa7dd-6608-466c-a68c-f41c59811c05.filesusr.com/ugd/ae15ca_fd15a31a9901460e9a3bd501d8026c08.pdf?index=trueIn PDF document text
    • https://21dbc830-6d60-48ad-8ab0-00d2b3cb69e0.filesusr.com/ugd/18d949_78f2761844544f8f81372403cb157569.pdf?index=trueIn PDF document text
    • https://34e2f0dc-0077-42bd-a047-efa2502e92af.filesusr.com/ugd/8a05ec_395472ef76d64dbeb67a5411e87b8818.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/perurulexi/jupexituli.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000103d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103D0 5928 bytes
SHA-256: 023a3c0bd7dc944b2899d031bcf12e0dbd220973a0a64bb2111c92c42aa62772
font_01_sfnt_off000117fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117FB 10900 bytes
SHA-256: 99c274ef31919f3e81013a905fe12bd28701e187aa2726e9ccc683175af58536