Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bd4994b79af81a4…

MALICIOUS

PDF

87.2 KB Created: 2021-08-12 10:18:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 3eaa6dcb645dd4fa574384ea8d21ff88 SHA-1: 3dcb487314c94b0226bc47701f78eb948addf0ab SHA-256: 8bd4994b79af81a4230fc8e147bf686b02bce79b7549a67f0c97272a5515a8ca
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://nwmanagement.ru/generic/uploaded/file/64405384531.pdf In PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160bc50dc8ed0b---guligazaluzonera.pdfIn PDF document text
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/1p2uu57jj7vtdd8l9k3h7hmnpp/79566273633.pdfIn PDF document text
    • http://fongyoskert.hu/userfiles/files/82092502622.pdfIn PDF document text
    • https://inverpalmas.site/aym_image/files/binovetosesuloraremevexi.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609f7853dac18---70605245659.pdfIn PDF document text
    • https://rocksoliddesigns.biz/userfiles/file/39914936695.pdfIn PDF document text
    • http://monkey-do.net/userfiles/file/mifegolafitivojagopezetob.pdfIn PDF document text
    • https://socialchangefactory.org/wp-content/plugins/super-forms/uploads/php/files/3321c80c00f2efda4749391266313f6a/ginewododota.pdfIn PDF document text
    • http://tantos.jp/js/upload/files/wodamif.pdfIn PDF document text
    • http://baohanhranghm.com/upload/img/files/40311115790.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160948f3ee179c---gotalofokumirinuja.pdfIn PDF document text
    • http://topas.lt/userfiles/file/nusaserugigoguwixed.pdfIn PDF document text
    • http://georgekoldun.com/var/upload/file/34598606166.pdfIn PDF document text
    • http://www.dawnrotaryclub.tw/UserFiles/files/sumuvoxewim.pdfIn PDF document text
    • https://tranduongauto.com/app/webroot/files/images/pages/files/munubib.pdfIn PDF document text
    • https://valserve.in/web/k/main_admin/ckfinder/userfiles/files/4076034145.pdfIn PDF document text
    • https://www.kadinlarsitesi.org/wp-content/plugins/formcraft/file-upload/server/content/files/16084fd2b5044c---40180836949.pdfIn PDF document text
    • http://mopi.eu/ckfinder/userfiles/files/83259432828.pdfIn PDF document text
    • http://zeroseistudio.eu/userfiles/files/tuvuzedukirosovuw.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/bhdvdjjnammv671d4m6g2vcb3l/pezisidazeka.pdfIn PDF document text
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/ad4795774eaebe8a24bf34cbff7cf7f1/kozame.pdfIn PDF document text
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160a419d853df1---45628840291.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=cfmoto+cforce+800+oil+changePDF 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_off0000efc6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFC6 10976 bytes
SHA-256: 11abd3a3a1ccd71f12da40d619b3ecc009163433cb86a0661cfe51213c82520a
font_01_sfnt_off00010917.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10917 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012129.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12129 16704 bytes
SHA-256: 6a36d1a0d98f8720673e5d22e83648488cdd5362e175b58dba54e78478fccf05