Malicious PDF — malware analysis report

Static analysis result for SHA-256 1737d4d2103c939e…

MALICIOUS

PDF

71.7 KB Created: 2021-09-03 06:48:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 571005bf057a9fff98613525e60a1b6a SHA-1: e202ac5d7edca035965c9787706a8e7ff478bd90 SHA-256: 1737d4d2103c939eca8ee9e89908df1df82e3224c17ecf984ea10f8ea3d0a045
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URIs point towards an attempt to leverage external resources for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b12748900c---tixejepaxizudabisidek.pdf In PDF document text
    • http://tnmetalworks.com/images/files/13295298393.pdfIn PDF document text
    • https://yz-yongzhong.com/upfiles/editor/files/97157119152.pdfIn PDF document text
    • https://villadorottya.hu/uploads/frontend/files/zaripot.pdfIn PDF document text
    • https://asiapharma.la/files/files/68832429429.pdfIn PDF document text
    • http://wisewood50th.com/clients/3/35/35ca2b70ae131fa39667c240906a3fe4/File/54757504398.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ed99cf3aa4f---gawabes.pdfIn PDF document text
    • http://www.pantonerestauri.com/ckfinder/userfiles/files/lefibarokesonaxogi.pdfIn PDF document text
    • http://invismortgagebroker.com/images/file/73190746646.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/c943ca6b8ac8c9bccccd3442076c04ee/fudalonunijununabi.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16119b5a667472---14572209961.pdfIn PDF document text
    • http://www.asejnrtigers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608ef8a46cbd4---suzitekasaxurejafedazi.pdfIn PDF document text
    • https://tiklatakip.com/calisma2/files/uploads/lafenom.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a341aaa5e14---zazivifesakad.pdfIn PDF document text
    • http://stratford1980.com/clients/1/19/19838be1bbe5684469623718d5e25b5d/File/50466387631.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=physics+formula+book+for+neet+pdfPDF 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_off0000b320.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB320 11332 bytes
SHA-256: 042467cd00e8dc32887cf5b3daf8d1ab5172ea496d7f3b3697f61309ab8f8b62
font_01_sfnt_off0000cd71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD71 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e583.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE583 17196 bytes
SHA-256: 7eb866121470a1d5fd3fb602f6fd708c411c8c10a298b5a69ac9a5238df8d29f