Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a40e91c28a4dffc…

MALICIOUS

PDF

80.3 KB Created: 2021-09-14 02:49:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 4d823aa8ab44c7f799dd99dbc4e1a5af SHA-1: 79f8b4d0a3f5fc8fd9d8ee4d3f78a7824cc53ded SHA-256: 5a40e91c28a4dffc4f69349f83a54fb456a2f87f82ec27375ec47f9ed4b8ef0b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier indicating maliciousness. The presence of numerous external URIs, many pointing to disposable domains and configured as a link farm, strongly suggests a phishing or malware distribution attempt. Although no scripts were explicitly extracted, the PDF structure and the nature of the URLs indicate it's likely designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 5

  • 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 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://lussoleathertiles.com/test4/EDITOR/example/v2/userfiles/file/97979592955.pdf In PDF document text
    • http://bfttacg.marketsearching.com/upload/files/65929627287.pdfIn PDF document text
    • http://thewesternmist.com/userfiles/file/99396300136.pdfIn PDF document text
    • https://satnamunicipalcorporation.com/admin/ckfinder/userfiles/files/16452869067.pdfIn PDF document text
    • http://serbanindustrialconstruct.ro/uploads/files/27602674057.pdfIn PDF document text
    • http://dtyxbpzx.com/filespath/files/20210902063209.pdfIn PDF document text
    • http://gearcon-eng.com/file_media/file_image/file/15310212573.pdfIn PDF document text
    • http://vuatoyen.com/uploads/userfiles/file/jogalari.pdfIn PDF document text
    • http://letsfinal.com/userfiles/file/rikazulewatunokek.pdfIn PDF document text
    • https://acp-luxusingatlanok.hu/ckfinder/userfiles/files/kesoxilibinad.pdfIn PDF document text
    • http://lysfyyy.com/upload/files/fedikonolelidinodumite.pdfIn PDF document text
    • http://dc-a0dcf319a153.breakthroughsport.com/userfiles/files/81437352191.pdfIn PDF document text
    • https://www.loisirs-auto-occasion.fr/ckfinder/userfiles/files/75120575135.pdfIn PDF document text
    • http://vektorma.ru/uploads/assets/file/zokogumutaw.pdfIn PDF document text
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/0cf91864f9ad6a2891e414377b7941f4/bafevuraminu.pdfIn PDF document text
    • https://geniodelweb.com/file/73910378086.pdfIn PDF document text
    • http://coomargroup.com/ckfinder/userfiles/files/65299555595.pdfIn PDF document text
    • http://www.impactit.in/ckfinder/userfiles/files/32475258094.pdfIn PDF document text
    • https://maxflowfans.com/userfiles/file/35241546781.pdfIn PDF document text
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/df1d665218766b4d9fb1d01757afb072/tetukalo.pdfIn PDF document text
    • http://eastendmediation.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/42796624757.pdfIn PDF document text
    • http://lovec.bg/root/ckfinder/userfiles/files/30496815619.pdfIn PDF document text
    • https://pesonabali.dswip.com/ci/userfiles/files/52662755899.pdfIn PDF document text
    • http://tiga.co.th/ckfinder/userfiles/files/54373176999.pdfIn PDF document text
    • http://urduhadith.org/survey/userfiles/files/tepetixa.pdfIn PDF document text
    • http://nuovartea.eu/userfiles/files/gimoliperutavelabidot.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=big+front+apkPDF 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_off0000d3aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3AA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ebc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBC1 10332 bytes
SHA-256: b8436ca16ec1ef84ba125c85dc9837c62a36e88e3e6ea1b8e6be5be15da06c0e
font_02_sfnt_off00010334.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10334 18384 bytes
SHA-256: a7dd74d7445fd0161c98f936c4fa7805239a3f2f585a571901cf5e1dce365cb7