Malicious PDF — malware analysis report

Static analysis result for SHA-256 213af55623e0f9da…

MALICIOUS

PDF

83.5 KB Created: 2021-09-14 09:18:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 2fda63bb50f587d1f0f0ccbf7b8b6eb4 SHA-1: 822902cc313f61b8808ff9deae4c4eb3ed92e60a SHA-256: 213af55623e0f9dad8e62a235417fbc7f4ce54cf59f2f6de3111e6641c602a05
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the URL structure and heuristic firings are sufficient to infer a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://coretry.ru/uplcv?utm_term=picsay+pro+mod+apk+free+download PDF link annotation
    • http://cafehinglung.com/uploads/files/71858199899.pdfIn PDF document text
    • https://cahayaapi1.com/contents/files/35379552081.pdfIn PDF document text
    • http://car-zone.sk/data/data/file/makixibefozuken.pdfIn PDF document text
    • http://leebyunghun.org/new/upload/board/files/wibovumajolesisemi.pdfIn PDF document text
    • http://africareview.in/userfiles/file/xupovemabuzeped.pdfIn PDF document text
    • http://juha.be/_files/file/38277798783.pdfIn PDF document text
    • http://unionnutritech.com/upload/files/33719899695.pdfIn PDF document text
    • https://youxsoft.com/uploads/files/duvolexenipera.pdfIn PDF document text
    • http://usa-ex.com/images/blog/file/48627799030.pdfIn PDF document text
    • https://muzpony.de/obrazki/file/85563212261.pdfIn PDF document text
    • http://terezmisszio.eu/files/file/xotatubutujagodezaba.pdfIn PDF document text
    • http://hantechwelding.com/userfiles/file/2021091402472773499.pdfIn PDF document text
    • http://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/e72fda635af81e5d9e1a99ae9493a5c6/55242687709.pdfIn PDF document text
    • http://www.verneteco.com/ckfinder/userfiles/files/91118007112.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16140087551673---41011292084.pdfIn PDF document text
    • http://aytekinpolatel.com/image/files/39664311279.pdfIn PDF document text
    • http://playoz.com/ckfinder/userfiles/files/28933307848.pdfIn PDF document text
    • https://evergreencans.com/userfiles/file/tulatodasex.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613ee13d1d6a8---finunolikuwegidej.pdfIn PDF document text
    • http://dostrojar.sk/UserFiles/file/23896058573.pdfIn PDF document text
    • http://chiron-ventures.com/chiron/home/img/upload/files/210913214654464454xizm5.pdfIn PDF document text
    • https://techielingo.com/fck_uploads/files/99954410794.pdfIn PDF document text
    • http://jrecchina.com/ckeditor/ckfinder/userfiles/files/22516343804.pdfIn PDF document text
    • http://jfe.hk/userfiles/wijakewewuzewuvimikokeno.pdfIn 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://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_off0000e156.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE156 17504 bytes
SHA-256: cce44822986b937247f3523ae16e39ddffd2debff802b6c02efa8b831eea943c
font_01_sfnt_off00010e9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E9A 10976 bytes
SHA-256: 01a6824e5951338fe54d07d12f995448e850b24a407f2ad30e25db59f3c9c57e
font_02_sfnt_off00012829.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12829 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1