Malicious PDF — malware analysis report

Static analysis result for SHA-256 da16cc81e2a85e91…

MALICIOUS

PDF

73.1 KB Created: 2021-09-14 03:30:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 84be2da0e6a6beae3ed3e8ee91040b5b SHA-1: cb14e5df59d59b812e4ac1fe629d1da3d9f7bd99 SHA-256: da16cc81e2a85e918a437862ac0b26d580957c2d9017d6b04a8e206b7e9fc41c
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple potentially compromised or malicious websites. The presence of numerous unknown URLs, many hosted on disposable domains, strongly suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/0b1odrqu4ofi00uf5ud76h9do4/fiwusemit.pdf In PDF document text
    • https://koratspring.com/upload/file/fuxaviruti.pdfIn PDF document text
    • https://quanticabtl.com/cms_2018_quantica/sgi_userfiles/userfiles/files/wovigifiralulowobi.pdfIn PDF document text
    • https://dafelia.com/files/tiputunuvafunugewovuke.pdfIn PDF document text
    • http://kingkady.cn/uploadfile/files/putup.pdfIn PDF document text
    • http://thaifilmind.com/UserFiles/file/rebetazorasop.pdfIn PDF document text
    • http://bachtungcompany.com/upload/files/70468124594.pdfIn PDF document text
    • https://elesud.it/img_pagine/file/vaxoxame.pdfIn PDF document text
    • http://jewelry-shopping-city.com/uploads/files/202109010808349729.pdfIn PDF document text
    • https://nacituran.com/userfiles/file/14146873840.pdfIn PDF document text
    • http://bitite.lv/media/txt/122/file/zidifidusonij.pdfIn PDF document text
    • http://osteriailgalloelinnamorata.com/userfiles/files/789495867.pdfIn PDF document text
    • https://mb-classic-service.de/userfiles/file/mimaridelojotunomokuna.pdfIn PDF document text
    • http://arucax.am/user_images/file/tubazovulosiz.pdfIn PDF document text
    • http://elcivan.com/admin/UserFiles/file/ludabufiluwigosudub.pdfIn PDF document text
    • http://newgrids.com/userfiles/file/wemivitos.pdfIn PDF document text
    • https://argekaucuk.com/nbg/upload/files/48015971955.pdfIn PDF document text
    • https://protum.se/file/73194105969.pdfIn PDF document text
    • http://nobody-films.com/bpms/includes/fckeditor_uploads/userfiles/file/debadakemoxiniv.pdfIn PDF document text
    • https://franchiseharbor.com/files/files/21802751001.pdfIn PDF document text
    • https://abisspaandboutique.com/nbloom/fckuploads/file/76177620356.pdfIn PDF document text
    • https://fiberglasssupplydepot.com/userfiles/file/96679574514.pdfIn PDF document text
    • http://compagniaviaggi.gattinonimondodivacanze.it/themes/userfiles/files/jenujugabuparewudemuf.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fd21e37110---vanufowolawikusubokamod.pdfIn PDF document text
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/0o00tjv2bpm1ps1r0p3pogu9n0/22423044117.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=mafikizolo+emlanjeni+mp4+downloadPDF 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_off0000b8f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8F3 17448 bytes
SHA-256: 37221b1a7e49c9b17116467260efff3dea2f1fcc4dcc4dda706336f90d552a78
font_01_sfnt_off0000e64c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE64C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fe63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE63 10732 bytes
SHA-256: b8a448dc78e3976c76b124608db23efcbab5f7f22431b4b4bb17b8979b27ae3d