Malicious PDF — malware analysis report

Static analysis result for SHA-256 5bca9908acfc70d9…

MALICIOUS

PDF

84.1 KB Created: 2021-09-19 23:44:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: cb6875ced837f889c81147a4a1024a5c SHA-1: a2c3c42a62267156cef2caa0f81e881e2ea5ca9f SHA-256: 5bca9908acfc70d93fe1143b9cb79f27f4af449c749c33c01519d67423121097
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm. Multiple URLs point to compromised WordPress sites, suggesting an attempt to lure users to malicious content. The PDF structure and embedded links are consistent with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1612fc28088383---lifozukibetibebil.pdf In PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/161405d565fadb---63287953503.pdfIn PDF document text
    • http://angelascanu.it/uploads/file/52311677903.pdfIn PDF document text
    • https://transilvaniafishing.ro/app/webroot/files/userfiles/files/tunevaso.pdfIn PDF document text
    • http://airzo.net/userData/board/file/nurarikafobisutagugiroja.pdfIn PDF document text
    • https://fluffy-chins.com/images/file/kuduzat.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/xikawuzineleriwifune.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136355d118fb---zewud.pdfIn PDF document text
    • http://basaritarim.net/admin/editor_resim/file/zejusanodize.pdfIn PDF document text
    • http://i-dron.cz/data/file/wovelapopikemovi.pdfIn PDF document text
    • https://rainbowfurnitures.com/files/files/69854614388.pdfIn PDF document text
    • https://isigakizima.net/img/tmp/file/20741717445.pdfIn PDF document text
    • http://tivatijapan.com/uploads/userfiles/file/28214281127.pdfIn PDF document text
    • https://piphoto.tw/uploads/files/202109181601307464.pdfIn PDF document text
    • http://zhongguohuachun.com/d/files/45682974743.pdfIn PDF document text
    • http://mdtrend.hu/files/file/sufanabipawuwutejo.pdfIn PDF document text
    • https://numen-wow.com/userfiles/cloud/files/xegezafis.pdfIn PDF document text
    • http://odesignlab.ru/admin/ckfinder/userfiles/files/rasufirosibol.pdfIn PDF document text
    • http://keralatravelpath.com/uploads/file/romuwelixeputim.pdfIn PDF document text
    • https://totalsewa.com/userfiles/file/82216916805.pdfIn PDF document text
    • http://cerrutistudio.eu/userfiles/files/kujekivukizonowonivugo.pdfIn PDF document text
    • https://www.ijmsir.com/ckfinder/userfiles/files/99020061817.pdfIn PDF document text
    • http://lexen.ca/userfiles/files/58704535815.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=force+effect+app+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_off0000e4f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4F9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD10 10376 bytes
SHA-256: c86ccd476eb2b1de707062399550dce5ba3d2450ef1237bc01341f70c30bfcef
font_02_sfnt_off0001149a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1149A 18056 bytes
SHA-256: 010ab80c89b9d2f81fb225132c79c52ac118ba9b4ffcc9fa460822b1dbca5173