Malicious PDF — malware analysis report

Static analysis result for SHA-256 2b56d6fcee90fc4a…

MALICIOUS

PDF

161.3 KB Created: 2021-07-03 13:53:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 59461c416a26d3b1ade7014823977a04 SHA-1: 8bf54922f108515b2b1fe0aba11d9ce0499a76d8 SHA-256: 2b56d6fcee90fc4ad6ba99df0970bc829d142cd3fbdd37846089ed55323c9fc4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many 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 link farm heuristic point towards an attempt to leverage embedded links for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9918

Heuristics 6

  • 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.
  • 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://zaun-produzent.de/userfiles/file/73289379916.pdf In PDF document text
    • http://sllight.ru/design/img/upload/file/1196361517.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/89b69f9c15f648e9c0cbd26c3fb2cbd4/devebijivazifuxepamubid.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bcd449ad8b4---34849626146.pdfIn PDF document text
    • http://unicorn-furnitures.com/d/files/nanejedezabedikule.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084d09e37e14---bivirijobukul.pdfIn PDF document text
    • http://cnokorea.com/userfiles/file/rubedumuga.pdfIn PDF document text
    • https://www.propertyfilevault.com/wp-content/plugins/super-forms/uploads/php/files/57621818f9973c9a83c858c26521537f/faserabewe.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/160745ec74c941---karewisa.pdfIn PDF document text
    • http://gentlemensquartersbarbershop.com/wp-content/plugins/super-forms/uploads/php/files/f28d67f7557d23923aeb17c901d6e48a/logesoviwelix.pdfIn PDF document text
    • http://pantryscan.com/123cars/imagefck/file/93402173773.pdfIn PDF document text
    • http://xn--80aejmo0alc.xn--p1ai/ckfinder/userfiles/files/23713141484.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607a34b8c50a6---578003988.pdfIn PDF document text
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/fdd1f173a6afdd73d321e399edc8d30b/83537695352.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f83ccb086a---lilufote.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=english+vocabulary+in+use+key+answerPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001fdfa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1FDFA 16140 bytes
SHA-256: 00b1f632e8afe72716c8bcdb76b7901b56c060d1dc0f96f3f5c1b8373b85735b
font_01_sfnt_off00021377.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x21377 10992 bytes
SHA-256: aa2acb3b537af771ab0de027ac4045a2a35daa1257439fb191b79b9a35a3e2a0
font_02_sfnt_off00022d00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x22D00 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off00024512.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x24512 19012 bytes
SHA-256: 6f2c6ce657f43d8ed9eeabc02b0c9ead96e329be57d0f9e4a252df67cfe7ff98