Malicious PDF — malware analysis report

Static analysis result for SHA-256 b0ab8e2bdd5b7b45…

MALICIOUS

PDF

84.6 KB Created: 2021-09-08 20:15:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2b531e3226e5a5c2bfd7d1c1e31fe6dc SHA-1: cbe2826ab5579b74452083b8e9a400439a64fdae SHA-256: b0ab8e2bdd5b7b4553e85a3ef25563daaf6735380ab89a503a123bc9dc6f9229
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for malicious PDFs to execute code or redirect users. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM indicates the PDF is part of a link farm, and the presence of numerous unknown URLs supports this. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution through a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://fsoa.cn/userfiles/file/fimitusit.pdf In PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613273ccee2d3---vifinugevujijajadewetix.pdfIn PDF document text
    • http://addon-colsman.somantec.net/ckfinder/userfiles/files/rurewenasuputegodawete.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/d42389f62a0228367933c043cee06ddf/tunukefajezaxofedurobow.pdfIn PDF document text
    • http://speckletrack.com/update/editor/file/67277713534.pdfIn PDF document text
    • http://askaudit.ru/price/76936707008.pdfIn PDF document text
    • http://madveras.com/ckfinder/userfiles/files/6553182222.pdfIn PDF document text
    • http://cachnhietwin.com/luutru/files/97049189701.pdfIn PDF document text
    • http://kiiga.ru/userfiles/file/13354133792.pdfIn PDF document text
    • http://zopos.zohukum.com/ckfinder/userfiles/files/rezaxanujarivevaxi.pdfIn PDF document text
    • http://bjerkelunden.org/content/files/userfiles/file///kajifosojopuwigalinala.pdfIn PDF document text
    • https://piataafacerilor.ro/app/webroot/files/userfiles/files/zojipu.pdfIn PDF document text
    • https://ever.dacola.com/upload/files/83568570168.pdfIn PDF document text
    • https://www.hotelrestaurantmacarena.fr/ckfinder/userfiles/files/bifosima.pdfIn PDF document text
    • http://trubaopt.ru/content/file/gomoguxigitadanu.pdfIn PDF document text
    • http://geodez.com/pliki/file/47290333291.pdfIn PDF document text
    • https://waxparadise.pl/userfiles/file/89640028114.pdfIn PDF document text
    • http://pcccmiennam.com/media/ftp/file/3981307215.pdfIn PDF document text
    • http://smflow.in/admin/uploads/file/23127989936.pdfIn PDF document text
    • http://hiace-yoshikawa.com/js/upload/files/53677544585.pdfIn PDF document text
    • http://pappteam.hu/userfiles/file/19223149245.pdfIn PDF document text
    • http://2m-m.eu/userfiles/files/kesawadogepewavu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=prevencion+y+control+de+tuberculosis+pulmonar+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_off0000dfb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFB8 19528 bytes
SHA-256: 02f5218315330c2401b3d8ce599d5fafc30c24ffaa06ea9516edb23d37814fad
font_01_sfnt_off0001128f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1128F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012aa6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AA6 11200 bytes
SHA-256: 0e019b9ab3befc3b2ffd3255c2eb300440f0e3fd8b8ab93e44b6f9f1f6720c31