Malicious PDF — malware analysis report

Static analysis result for SHA-256 40879db4120e6b75…

MALICIOUS

PDF

85.5 KB Created: 2021-09-14 08:51:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 240d3c552d065326f55139cb6ae85278 SHA-1: 508b2a8ca76b2f04a6b4eb1f50ad79d3acd6be72 SHA-256: 40879db4120e6b7559c5969dd2931a6d43ac011bbf24603db3466ffbe5630f99
134 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to suspicious PDF files on disposable domains, indicating a link farm designed to obscure the true malicious destination. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. While no scripts were directly extracted, the PDF structure and URL patterns are consistent with techniques used to distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://vico-immobilien.com/ckfinder/userfiles/files/nowexiwetibowez.pdf In PDF document text
    • http://www.egymast-segito.hu/uploaded/fck/file/50132151475.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612feecd369bb---27007522238.pdfIn PDF document text
    • http://szermgrt.hu/uploads/ckfinder/userfiles/files/3279527350.pdfIn PDF document text
    • http://hrzservices.com/uploadfiles/file/28815212996.pdfIn PDF document text
    • https://jagamimpi.net/contents/files/polozu.pdfIn PDF document text
    • http://wacommerce.net/home/integrity/public_html/ckfinder/userfiles/files/woteg.pdfIn PDF document text
    • https://trade.inter-ural.ru/ckfinder/userfiles/files/23571296457.pdfIn PDF document text
    • http://chapaconoticias.com/assets/ckfinder/core/connector/php/uploads/files/zobutelinovamuzad.pdfIn PDF document text
    • http://www.ppk-kp3k.kkp.go.id/ver2/extra/ckfinder/core/connector/php/media/ckfinder/files/ripokamopijunuruj.pdfIn PDF document text
    • http://herbwaterthailand.com/userfiles/files/mabada.pdfIn PDF document text
    • https://invision.buzyhub.com/files/91791163264.pdfIn PDF document text
    • http://erodiertechnik-wenzel.de/userfiles/file/39842978423.pdfIn PDF document text
    • https://grandplaza.bg/uploads/assets/file/98479677930.pdfIn PDF document text
    • http://patp1ryb.ru/media/file/dowobojokaloni.pdfIn PDF document text
    • https://jotelek.hu/files/file/37715108956.pdfIn PDF document text
    • https://majubesar.com/contents/files/14159112947.pdfIn PDF document text
    • http://aallergy.netlovestories.com/upload/files/futiw.pdfIn PDF document text
    • http://grafosaleservice.cz/images/fck_editor/file/5145614358.pdfIn PDF document text
    • http://safetyassessmentsolutions.co.uk/ckfinder/userfiles/files/salefepaxakuka.pdfIn PDF document text
    • https://medicabg.com/uploads/wysiwyg/files/7513964877.pdfIn PDF document text
    • http://shiokuda1.com/contents/files/xefomalu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=predator+hunting+grounds+download+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_off0000dd53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD53 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f565.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF565 21676 bytes
SHA-256: 9b8054336bda877d51c29db3388036c74e633e5c6ad37b0a9f47f383bc9a9643
font_02_sfnt_off00012e31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E31 10712 bytes
SHA-256: 5b509338b39df7fa4720e33c73f2bd0c44b47e5906634046257dadd550b13e16