Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4afb797cf3d39d9…

MALICIOUS

PDF

83.0 KB Created: 2021-09-18 03:22:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 8d353fc0bdfda64747b52a05dafa501f SHA-1: 1dfe91cfd38ea76c63e7c7021a5a7c188af4cdda SHA-256: f4afb797cf3d39d953604cc97a9d2336c55aa8bc755df8c97340fb74220df47f
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple websites, some of which appear to be compromised CMS uploads. The heuristic 'SE_PASSWORD_ARCHIVE_LURE' indicates the document likely instructs the user to open a password-protected archive, a common tactic to bypass gateway security. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/98623681418.pdf In PDF document text
    • https://ndmoyun.com/calisma2/files/uploads/11078464903.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/16144db87b988c---bopigadop.pdfIn PDF document text
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/65e70db371c065e40746e890784b06bb/60018009444.pdfIn PDF document text
    • https://semagro-msw.ru/pics/images/file/zewobelunotosikejidena.pdfIn PDF document text
    • http://tbff-bygg.se/img/files/90572209394.pdfIn PDF document text
    • http://bdsps.org/slbdavbatala/userfiles/file/pivirakageroga.pdfIn PDF document text
    • http://irinabailey.com/upload/files/rukukisa.pdfIn PDF document text
    • http://studiobaliva.eu/userfiles/files/23847931834.pdfIn PDF document text
    • http://bielle-srl.com/userfiles/files/vagivipepowo.pdfIn PDF document text
    • http://paradisetourkorea.com/FileData/ckfinder/files/20210909_53F5C08BC86AC1AE.pdfIn PDF document text
    • http://gps-ambroisie.com/ressource/site-image/files/10596026023.pdfIn PDF document text
    • http://cn-polylysine.com/d/files/sipipumuvitukepavevepufef.pdfIn PDF document text
    • http://rulife.ru/ckfinder/userfiles/files/kewadowisu.pdfIn PDF document text
    • http://bagliodeimille.it/userfiles/files/kexinofomin.pdfIn PDF document text
    • http://royal-pizza.eu/files/file/13489551519.pdfIn PDF document text
    • http://scuolascifondocortinadolomiti.it/userfiles/files/81896344740.pdfIn PDF document text
    • https://millinerandassoc.com/files/file/xekamijituxaxozuxe.pdfIn PDF document text
    • https://vjlabor.pitscovn.com/uploads/Upload/files/wuruziburine.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/16141eb8bc80e1---wejulosemefevodavevuli.pdfIn PDF document text
    • http://effektfilm.de/files/file/9112012650.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=how+to+play+cbr+files+on+androidPDF 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_off0000e0b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0B0 16980 bytes
SHA-256: cabcc1eef2080c09ef598467af7de5487e4112f0d186a070faefdd63ee1126ac
font_01_sfnt_off00010c8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C8D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000124a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124A4 10944 bytes
SHA-256: cde26c50ed91da5b65d3e1ffbfad0a26ec1a28fde6f92f73276143d1686a1aaf