Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd11bc97f6b7bf10…

MALICIOUS

PDF

84.7 KB Created: 2021-09-06 10:48:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 614def17e33969d94a3ad65734ac151f SHA-1: ab1402b59e74a2a44806d12825853c9818564a83 SHA-256: bd11bc97f6b7bf10aafaf1a1f7b89f015e3145beb3a8277535946e1ca37fa108
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. The presence of multiple heuristics related to link farms and compromised CMS uploads, along with a high ML classifier score and ClamAV detection, strongly indicates malicious intent. The embedded JavaScript likely facilitates the redirection to malicious URLs, as evidenced by the numerous external URIs found.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://hoangminhsaigon.vn/@dmin/js/ckfinder/userfiles/files/12435417573.pdf In PDF document text
    • http://annandale1963.com/clients/69704/File/33586292125.pdfIn PDF document text
    • http://giasuminhtam.com/Images_upload/files/zolevemepawute.pdfIn PDF document text
    • http://arcdesantmarti.com/biocop/Images/images-editor/file/pepepibitapu.pdfIn PDF document text
    • https://nsck-cykelmotion.dk/userfiles/file/98403485857.pdfIn PDF document text
    • http://rcot.by/pics/files/36642688215.pdfIn PDF document text
    • https://rainbowfurnitures.com/files/files/bafonamuzuwurafevugux.pdfIn PDF document text
    • http://olimpic.hu/ckfinder/userfiles/files/45523184636.pdfIn PDF document text
    • http://pooq-design.com/app/webroot/fckfiles/file/wenotonajinezezikebok.pdfIn PDF document text
    • https://ev-owners.jp/userfiles//files/gotijuvematibo.pdfIn PDF document text
    • http://kiuanai.com/userfiles/file/sujoberifarotojajojutus.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/160b9259a1a1ca---68509125349.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/160d918d73b795---bodomirozimovatutiv.pdfIn PDF document text
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/283d8b0e6b4e27bc70f4e8bd260082d8/85455667702.pdfIn PDF document text
    • https://megashina24.ru/files/files/39329804326.pdfIn PDF document text
    • http://thesciencenetwork.org/uploads/files/bunovumumuk.pdfIn PDF document text
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/bc94bb490c686497cd3f8ebe16637e13/91499841928.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=apostila+de+portugues+ortografia+pdfPDF link annotation
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a901537ee9f---78491058411.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_off0000df13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF13 10652 bytes
SHA-256: 3f58c773880d16b0dcf5951b61f7ba9620f1454d659ac2abbf80daf6338a24a4
font_01_sfnt_off0000f769.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF769 21428 bytes
SHA-256: 0d67a809478c32e86c8f8bae9a16898ebd60393af0f686192b0b51c3203895e3
font_02_sfnt_off00012d8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D8B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1