Malicious PDF — malware analysis report

Static analysis result for SHA-256 90dd51f7faebe22c…

MALICIOUS

PDF

72.6 KB Created: 2021-09-19 07:10:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: ad5d08d713766ef60e46521c83e9b869 SHA-1: b03c28e97e8834d799339903de76fd3d9162d197 SHA-256: 90dd51f7faebe22cdc6b8010b4123d6705237bfdee2e40ef5cf97661d152a4e1
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories, indicating a link farm designed to redirect users to potentially malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/b7dd139c162d5fc916da4a090783f7db/mozug.pdf In PDF document text
    • https://ms01bet.com/contents/files/56379566354.pdfIn PDF document text
    • https://priscar.com/documents/files/xakosidamawofor.pdfIn PDF document text
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142541e82bd2---vapeso.pdfIn PDF document text
    • http://cosmoscm.com/contents/files/76447453156.pdfIn PDF document text
    • http://rszm88.com/upfolder/e/files/20210909232915.pdfIn PDF document text
    • http://ketoanantamhcm.com/uploads/files/39723976023.pdfIn PDF document text
    • http://e-menu.hu/editor_up/xedimipifi.pdfIn PDF document text
    • http://retailpark.bg/uploads/wysiwyg/files/tivasagafaso.pdfIn PDF document text
    • http://arnoldbolingbroke.com/ckfinder/userfiles/files/75192578440.pdfIn PDF document text
    • http://canadianartistic.com/userfiles/file/50862557035.pdfIn PDF document text
    • http://www.rajpuc.pl/pics/file/81670717201.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16146470262873---xavixuzagub.pdfIn PDF document text
    • http://studiosiriosrl.it/userfiles/files/pamogobito.pdfIn PDF document text
    • http://emilybarnes.com/DEVELOPMENT/VERSIONED/emilybarnes/trunk/sites/default/files/file/49469074579.pdfIn PDF document text
    • http://huntland.hu/upload/file/widapogiso.pdfIn PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/77a244549faeaf70b96440fbe19c983d/25150326860.pdfIn PDF document text
    • https://aartipalette.com/userfiles/file/75747031792.pdfIn PDF document text
    • https://cashcruis.ru/wp-content/plugins/super-forms/uploads/php/files/39e92b1bdf059ba9a64ccbf4a9aaff12/nomigunu.pdfIn PDF document text
    • http://cheliabinsk.realxenon.ru/uploads/files/vuvuniwotifiruxazifudun.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161461297bcefc---11712945608.pdfIn PDF document text
    • http://elai.kz/upload/2021/09files/210911192018482200gycpu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=vpn+unlimited+proxy+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_off0000b8f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8F0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d107.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD107 10764 bytes
SHA-256: 1b34585c0117c6233f4708f2b4ff750df4abb9681f2078d83cf3bdfa7b5351a7
font_02_sfnt_off0000e9c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9C3 16860 bytes
SHA-256: 16be01059feb80d025567a149310413b9eb48d062247f5e83f196b3e65bd407d