Malicious PDF — malware analysis report

Static analysis result for SHA-256 50a12a05b1a98105…

MALICIOUS

PDF

77.0 KB Created: 2021-06-19 18:44:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: de6a85d5694c8245bc82b8cee1db8358 SHA-1: a8f9b5ac4b574817f4fe0a9e76b2216cee19eaae SHA-256: 50a12a05b1a981057bc4eb87518e17378a93321c19920ac22a98d495fe0f8c3f
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • 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://irlanc.ru/uplcv?utm_term=ginnen+upan+seethala+full+movie+download PDF link annotation
    • https://securitegenerale.tn/userfiles/file/wulotutusexid.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c39e67de463---38150434358.pdfIn PDF document text
    • http://www.franklinwebdesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6cf3591669---lijefatikemebupur.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609e421714bbc---sagizuvutasotoga.pdfIn PDF document text
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/160705f0f23a6c---83789916441.pdfIn PDF document text
    • http://portalcom-b2b.es/img/user///file/_0870456001620607519.pdfIn PDF document text
    • http://aaaexpressheating.com/userfiles/file/nukonuda.pdfIn PDF document text
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c962894c78e---13518214434.pdfIn PDF document text
    • http://aiskreunion.com/clients/b/b4/b417c2091670ce0b0d78f4b231aea02c/File/lisezodopikebesomeferu.pdfIn PDF document text
    • https://liantoong.com/archive/upload/files/49906410857.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ac4cbe01539---12052301.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/rbqij2h0ic76q5kjn87mtmn5a2/87781210456.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/l01cnj82ngqv3dr96pmmr7rv15/nuluzejusin.pdfIn PDF document text
    • https://voolabs.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084518f84a16---kutufofojagolotul.pdfIn PDF document text
    • http://gfb.it/upload/fck/file/putabugipufukova.pdfIn PDF document text
    • http://hud101.vn/webroot/img/posts/files/40670249647.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_off0000f053.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF053 5368 bytes
SHA-256: 8d900fa12980c07c1ed0f77621243c7ff4ea8cfd946e0ea656866573c6f428ae
font_01_sfnt_off00010289.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10289 10648 bytes
SHA-256: b2e88404c19be727c8003c9b8dd826b68d1a45c0cc330818150a57c3d7794393