Malicious PDF — malware analysis report

Static analysis result for SHA-256 31a61cebb1abb945…

MALICIOUS

PDF

82.3 KB Created: 2021-09-02 19:18:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-03
MD5: 93f2b56197b3f73ee5b35d3458c5b897 SHA-1: 76ca935930844b388d3f0ab76cd363c80787d51f SHA-256: 31a61cebb1abb945aa3a6f4756b0570f947b32d8347af1ab8d5225b226244206
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites used for hosting. Heuristics indicate this is a link farm designed to lure users to external sites. ClamAV detection and ML classification confirm its malicious nature, likely as a phishing or redirection tool.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077c10174051---56883363465.pdf In PDF document text
    • https://childconcern.in/trila/userfiles/file/50035359047.pdfIn PDF document text
    • http://ecolservizinettuno.com/userfiles/files/nivazifubuso.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/554a11c07919fe72436a35fd3954fd4e/zasajexinudegoz.pdfIn PDF document text
    • https://alshuka.ps/ckfinder/userfiles/files/benugirusoxewokaveneziwis.pdfIn PDF document text
    • http://navrattan.co/userfiles/file/70289194411.pdfIn PDF document text
    • http://esipro.fr/userfiles/file/jupifimiwipeles.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075e911eae91---69025623162.pdfIn PDF document text
    • https://feng-shuiworld.com/userfiles/file/21720914796.pdfIn PDF document text
    • http://marymo.ru/uploads/files/fexazekakonawotekukosale.pdfIn PDF document text
    • http://clinicaveterinariabilancino.it/userfiles/files/99883648098.pdfIn PDF document text
    • http://misterholidaysanprisco.it/userfiles/files/17998279535.pdfIn PDF document text
    • http://royalgroup.at/tmp/foremigidove.pdfIn PDF document text
    • http://carriewoodfamily.com/clients/5/5b/5b9f2fb360c4065436fb7fe1267c3612/File/96373392054.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/c45fafe162e788b0e757e8e865fe5121/1454755322.pdfIn PDF document text
    • http://xinyuemu.net/assets/202109/files/20210901065510273290.pdfIn PDF document text
    • https://grupahatak.pl/admin/_fck_files/file/navevozifunugozoxipudas.pdfIn PDF document text
    • http://tksvolga.ru/userfiles/file/zulipupekojupodom.pdfIn PDF document text
    • http://pinzimoniofiumicino.eu/userfiles/files/lijedazexanaxijidiborobew.pdfIn PDF document text
    • http://usaoxin.com/userfiles/2021-5/file/46548828660.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609bb74f829cb---38666120144.pdfIn PDF document text
    • http://smartcevent.com/clients/871459/File/zuzika.pdfIn PDF document text
    • https://i3mit.com/shopadmin/upload/files/88834894377.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/09226550e393247adf227549b595befd/disomekiguvavanetuworep.pdfIn PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/16076358c58ca6---lagoxujogefuzuderibegep.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=harassment+act+pakistan+pdfPDF 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_off0000dcda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCDA 10700 bytes
SHA-256: 28013d21df16c1bff77750b702e7f47898239171ff0d12f4d230a7ec7bdc8d28
font_01_sfnt_off0000f55e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF55E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010d70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D70 18020 bytes
SHA-256: 3ed0541e91568c0a10f515ee8989da283ca13c72878535a324486b8882cb6d77