Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8a4d7f20641dd22…

MALICIOUS

PDF

80.9 KB Created: 2021-09-01 22:28:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 9174ab4b1892b410c04292eef42023cb SHA-1: bd6db5b55a9c74209e6c92a334e04762f12f282a SHA-256: b8a4d7f20641dd22190b4337bcbcd56b8be04a62c0e39987795b27cad81a7e40
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to numerous external URLs, several of which are hosted on compromised CMS uploads or disposable domains. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM firings strongly suggests a tactic to distribute malicious content or phish users through these varied links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://medtek.vn/storage/file/dimuxatojiserokopidarixo.pdf In PDF document text
    • http://nissanotogovap.net/uploads/images/files/wilagopitoxelotado.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/187509b063376e0fefe46fe54ca1be2d/gitaburuvololajusilekabik.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609eadde9b03c---fesizikixegidimuxovobi.pdfIn PDF document text
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075cfe748217---75839085987.pdfIn PDF document text
    • https://renhedc.com/uploads/files/202108131803148642.pdfIn PDF document text
    • https://ocvirapuato.com.mx/wp-content/plugins/super-forms/uploads/php/files/716c348bf2ba90d58d3cb7c486578bd1/42613234080.pdfIn PDF document text
    • http://decaldankinh.net/upload/files/39741128303.pdfIn PDF document text
    • https://hashtag.school/userfiles/file/33989061317.pdfIn PDF document text
    • http://www.pzkexie.com/up_files/file/13570815651.pdfIn PDF document text
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8e9937288---17425732060.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/tebubabagezizojizalovi.pdfIn PDF document text
    • http://luijkzonwering.nl/image/file/77648363209.pdfIn PDF document text
    • http://bukharasuwanee.com/sites/default/files/file/72803142302.pdfIn PDF document text
    • http://forter.vn/hinhanh/file/bodilapotegidedenigoman.pdfIn PDF document text
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8f4d7c5d5c---12760124053.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609478888e450---sagubororolu.pdfIn PDF document text
    • https://everywheregenes.com/uploadfile/qu26_qu106_com/files/padeniri.pdfIn PDF document text
    • http://cnokorea.com/userfiles/file/pulob.pdfIn PDF document text
    • http://douzonebnf.com/upload/file///faferoxowuxogunabosujid.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=ingredients+for+water+breathing+potion+minecraftPDF 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_off0000d7c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7C1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000efd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFD8 11200 bytes
SHA-256: b41313a0b571ebc8705759e470086950b9270da58c2a136631a21b46486ca2c8
font_02_sfnt_off00010983.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10983 17128 bytes
SHA-256: 5a1d2de379b2f54f8f4f5ebda654d5cc5729e0096c7f2102fbc80db09a785d17

Open this report in the interactive analyzer, or submit your own file for analysis.