Malicious PDF — malware analysis report

Static analysis result for SHA-256 b87ba2405091dae5…

MALICIOUS

PDF

72.7 KB Created: 2021-08-01 23:41:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 764e1401014b9b98fd6d597ff76789bf SHA-1: 51a11f6ecf9b5d1ed4258026d2d623d6eeac3a23 SHA-256: b87ba2405091dae554137a3153924b0f8dd43c1d574f08c62a25c59d500f907f
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF is identified as a phishing lure due to its image-only nature and embedded clickable links. Multiple heuristics indicate it's a link farm hosted on compromised CMS uploads and disposable domains, designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely to lead users to a phishing site or download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 72 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/pulr39d7m98t4jee1vgunl76um/340504124.pdf In PDF document text
    • http://djpress.pl/Image/files/68989086348.pdfIn PDF document text
    • http://atel-j.nl/uploads/files/mojixamasebaxuzur.pdfIn PDF document text
    • http://mitcostruttori.it/userfiles/files/raxaxikuvuxub.pdfIn PDF document text
    • http://onlineticketreview.com/images/file/20855768096.pdfIn PDF document text
    • http://chupanhnoithat.vn/upload/files/96848051179.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160703f857a2f6---94200869134.pdfIn PDF document text
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16076a2c091d21---vesojujif.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ec4efe3cfe9---13146097697.pdfIn PDF document text
    • https://aeternoplanning.com/ckfinder/userfiles/files/91952679957.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/160b5c9821a68e---69724239288.pdfIn PDF document text
    • https://peterdegendt.be/file/66588215895.pdfIn PDF document text
    • https://regeneracion-capilar.com/wp-content/plugins/super-forms/uploads/php/files/1e87b85bf0d51fe47bfa6117292d3fad/rewubevaroxuzen.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/kmbc8f7dmhlj33jg317eet9s3p/wawuwa.pdfIn PDF document text
    • https://addsfly.com/userfiles/file/popodopitumiporujopadog.pdfIn PDF document text
    • https://sportsht.com/userfiles/file/83385459565.pdfIn PDF document text
    • https://flexrocksrollovers.com/wp-content/plugins/super-forms/uploads/php/files/lufg2m1lcfst0fquscnjihm2qe/parutuketezebanameromozuf.pdfIn PDF document text
    • http://mebizstekla.ru/userfiles/file/dajikuzaduva.pdfIn PDF document text
    • https://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/n89b07hj1buamvv1atb4tin949/7396224276.pdfIn PDF document text
    • http://aj-logistics.com/stock/userfiles/file/12819430228.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16094d08736d42---32935762602.pdfIn PDF document text
    • http://areaengineeringsrl.eu/userfiles/files/24685708707.pdfIn PDF document text
    • http://jsdarvin.com/files/48536805070.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fb6d60790e---gikuxaniwitatedonuretoz.pdfIn PDF document text
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/h03na1nd38t61f3fj4tpusb0nh/78637718418.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607e87db74d91---18120127810.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=volveria+a+mentir+evelyn+de+la+luz+tabPDF 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_off0000c191.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC191 13712 bytes
SHA-256: 687e83fdcb41a5154d1b6ed6534da9eed50d7c38a3d9669cce6d70bffc87c150
font_01_sfnt_off0000e360.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE360 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fb77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB77 10692 bytes
SHA-256: 7f1e3937ad8b7912737907f2ddb49f6db5ca0c755f9594dbd495ef0a0459123c