Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d3bfe073c55b5ad…

MALICIOUS

PDF

73.9 KB Created: 2021-06-22 18:51:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 2df2d10643ed5e36778030e70f76459a SHA-1: b894d32d5a9498d343f475adda744a7746557f0e SHA-256: 5d3bfe073c55b5ad82a67410f20ff48f7e99d52efab2770966073f0152f98c0a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains a link farm pointing to multiple websites, some of which are identified as compromised WordPress uploads. The primary URL suggests a lure for downloading 'brain out mod apk', indicating a potential phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly support the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://infrive.ru/uplcv?utm_term=brain+out+mod+apk PDF link annotation
    • http://al-bandak.com/userfiles/file/57785920353.pdfIn PDF document text
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608705056ce94---xisutegeval.pdfIn PDF document text
    • http://jagatjyotischool.org/jagatjyotischool/userfiles/file/98279949233.pdfIn PDF document text
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/7103c75fe813b5d50b788d2efb137224/lopobetunavuporalel.pdfIn PDF document text
    • https://cashmeredreams.com/wp-content/plugins/super-forms/uploads/php/files/06f5525c3d82e7c31773c98fe85287cf/rurajisasunedozitewanevol.pdfIn PDF document text
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/160bd31071b05b---besapuzefurojizosa.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f21f779cb6---8150476018.pdfIn PDF document text
    • https://777mto.org/contents//files/fugususezeditewik.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/11477d88b7146d127573a69dd1bc6a8b/xaluxadomumup.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c216cfa62d5---fuzebekiwasikanol.pdfIn PDF document text
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/e8c87fbc15688206382bebba1cdda09f/nofig.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070a3730a635---24184642186.pdfIn PDF document text
    • https://ipic.vn/userfiles/file/70713601746.pdfIn PDF document text
    • https://africanresearchcenter.com/userfiles/file/gusuwujowusunixenenu.pdfIn PDF document text
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/160b46098425ff---79917746578.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d9f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9F0 5008 bytes
SHA-256: b067b2ac9b53e958fe07620baf8b53df769f484591887054a21fdc10621cd5b4
font_01_sfnt_off0000eae5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAE5 21944 bytes
SHA-256: 54559e1f93d05a25e652a1c8e08866107e642fe9a9993f3b80fbff0f1a60978a