Malicious PDF — malware analysis report

Static analysis result for SHA-256 3cb41bfb8903aed8…

MALICIOUS

PDF

83.7 KB Created: 2021-09-17 07:47:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 31f52ceaf3beaaa21c5a479f8224ac1f SHA-1: 38455882fb88a6db5ef3332857bb132a57054872 SHA-256: 3cb41bfb8903aed819c891d06322b95c682a25e3e8d3cd0d8676303e283210e8
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with numerous URLs pointing to potentially compromised websites or disposable hosting. The presence of external URIs and link farm patterns suggests the primary goal is to redirect users to malicious sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://wastran.ru/uplcv?utm_term=sons+of+behemat+battletome+pdf+free+download
    • https://gullyracing.it/admin/ckfinder/userfiles/files/96440750082.pdf
    • http://www.bongbansaigon.com/uploads/files/12894925.pdf
    • https://spitalmoldovanoua.ro/ckfinder/userfiles/files/xadaferu.pdf
    • http://hrzservices.com/uploadfiles/file/914910525.pdf
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1612ea85f3809a---11297604733.pdf
    • http://club-integra.ru/userfiles/file/repiminogonaduzozowunaja.pdf
    • https://pustelnik-budownictwo.pl/ckfinder/userfiles/files/fosulafolabemogobageleg.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1612ef594c16a1---27432714050.pdf
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/55a31dedabec4ba8fc11f146aab66ad7/25532775563.pdf
    • http://nyitotthaz.hu/userfiles/files/lusose.pdf
    • http://wonderful-foods.net/userfiles/file/12223415163.pdf
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613e9b8661a0b---tukinovabeposadafupa.pdf
    • http://4reality.cz/userfiles/files/rokivavuzidumoxivoseg.pdf
    • https://webkapper.nl/ckfinder/userfiles/files/17017211744.pdf
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/161373bd0a7fce---sozumulebovokixokuzopo.pdf
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1614386ce97a31---23691603621.pdf
    • https://resttour.com/images/userfiles/files/2461217401.pdf
    • https://derechosenred.org/aym_image/files/tufazovoj.pdf
    • http://marcth.pl/media/fck/file/40481625313.pdf
    • https://clinicscrm.com/img/files/42221443817.pdf
    • https://nada70.org/userfiles/file/nekubizivakuzelasutex.pdf
    • http://zonwering-belgie.com/ckfinder/userfiles/files/36657193329.pdf
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/21699e9ab5ada82aac7ad478a32ac836/rumasavewow.pdf
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/2pijh7u1ib3su2kob8mkjn0r07/28317498898.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e2d6.bin
6d64aa39249f52725a86295d6a24d8423a6277c5af433078fec6e6ed1ce57137
pdf-font-stream PDF embedded font (sfnt) at offset 0xE2D6 17656 bytes
font_01_sfnt_off00010fcb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10FCB 16792 bytes
font_02_sfnt_off000127e2.bin
d412b653c442867280ad897b4b14ae6a02a2d33525270d0871031240e23b7f9a
pdf-font-stream PDF embedded font (sfnt) at offset 0x127E2 10972 bytes