Malicious PDF — malware analysis report

Static analysis result for SHA-256 e335c36408217a70…

MALICIOUS

PDF

92.3 KB Created: 2021-09-17 09:19:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: b9c47f588adff2dc52a7405c5ad76ff7 SHA-1: 2a18933d9a68d01770f09ff528364d29745afb2f SHA-256: e335c36408217a7032ef904ad65ecda8b646f41cc0537f5f9fe87540454ccff1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs that point to various domains, many of which appear to be compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document is designed as a link farm, potentially for SEO manipulation or to host phishing content. The presence of external URIs and link farms strongly suggests an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://crewmak.ru/uplcv?utm_term=import+pdf+into+excel+online PDF link annotation
    • https://artistprasanna.com/userfiles/file/22392878610.pdfIn PDF document text
    • http://indagosrl.it/userfiles/files/sufefibi.pdfIn PDF document text
    • https://aspirecambodia-edu.org/userfiles/file/1661361822.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130171d6f4b3---7115278433.pdfIn PDF document text
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/j3po6j6jes01559htdbhek9hg5/gozoxadurat.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143f08023642---61763954629.pdfIn PDF document text
    • https://amatnieks.com/pictures/image/fofijas.pdfIn PDF document text
    • http://hongpakthai.com/ckfinder/userfiles/files/16813248311.pdfIn PDF document text
    • http://daiduongmetal.com/uploads/ckfinder/files/13801453256.pdfIn PDF document text
    • http://ephtour.com/FileData/ckfinder/files/20210910_F00692BDCE44E234.pdfIn PDF document text
    • https://dichvuketoanvn.org/uploads/files/42561850740.pdfIn PDF document text
    • https://nbretail.com.vn/ckfinder/userfiles/files/limebemuxozozanazurux.pdfIn PDF document text
    • https://ivanda-commerce.hr/userfiles/file/98302842651.pdfIn PDF document text
    • http://kiiga.ru/userfiles/file/birukokodekubopex.pdfIn PDF document text
    • http://dr-temt.ru/images/file/nadaxoxatomekekitapebilu.pdfIn PDF document text
    • https://cr2tek.com/userfiles/Proj_Name/files/80034612798.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134df142a245---8519335287.pdfIn PDF document text
    • https://laundrybyconrads.com/nbloom/fckuploads/file/55701135112.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/16137e34772cd6---99722546318.pdfIn PDF document text
    • http://pinturasoltra.com/images/slider/files/71659233880.pdfIn PDF document text
    • http://huile-de-nigelle.info/userfiles/file/fupazoronowodonuvuj.pdfIn PDF document text
    • http://nail-free.com/ckfinder/userfiles/files/97970376254.pdfIn PDF document text
    • https://matrainagycsalados.hu/userfiles/file/69895930209.pdfIn PDF document text
    • http://www.hz-kontejnery.cz/ckfinder/userfiles/files/23445105430.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_off000103d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103D8 10504 bytes
SHA-256: 292c0786dc75ed0ac483c6c3851342fcc0d6a528a7307e0913f06e6b14de2f60
font_01_sfnt_off00011b9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B9E 18288 bytes
SHA-256: bf9d342018a272c351314a8189e700bed6046cd9e76fc36516db32ff9882c51a
font_02_sfnt_off00014b32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14B32 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1