Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf0759e0fbe213b4…

MALICIOUS

PDF

81.4 KB Created: 2021-07-06 23:33:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 677b6e1c19d2545a4abc51256b1e6bcb SHA-1: e3e5eb0b9092fbeec49b8804252cf39697e2b493 SHA-256: cf0759e0fbe213b4efeabd237821dd2a17d80f6ef770f8082d9490a6758af88d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous external links, many pointing to compromised websites 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 distributing further malware. Although no scripts were explicitly extracted, the PDF structure and link farm heuristic point towards an attack pattern involving user redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://qytbearing.com/upfile/file/10419262428.pdf
    • https://autotoner123.com/home/autotone/public_html/ckeditortest_WORKING/ckfinder/userfiles/files/40943326457.pdf
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/fd05188d9ade1ea6e843c534425b4772/tekimewunimofuvunarumim.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608f641052fda---xufiw.pdf
    • https://cedarcreeksauce.com/wp-content/plugins/super-forms/uploads/php/files/ae4bba0a850ecf43a54b3f5933831869/woporiginirebexeguwon.pdf
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607987b9260c3---dagatenojaxevibibulawas.pdf
    • http://musorcentrum.hu/files/article/file/95013286952.pdf
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/23205a19a7e08685a40bef290fe91660/15803376675.pdf
    • http://anatolianlgs.com/userfiles/file/31293432698.pdf
    • https://urbanplace.me/wp-content/plugins/super-forms/uploads/php/files/f98433cc4f6f438b5ab814d6bf1c15e4/kiverepinojevulovaba.pdf
    • http://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160a5d79c001fc---jazotuzu.pdf
    • http://premiercontractinginc.com/files/file/92611262516.pdf
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ce633712d0---leguxewaxuxurakofezor.pdf
    • http://sunjewelsonline.com/userfiles/file/fefexagaru.pdf
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16086e29c52a8f---9902105748.pdf
    • https://cutandcolorparrucchieri.it/file/42937888348.pdf
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/7b45f0faa7d059588f2c147fe3feb310/mizupexi.pdf
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080028c10ad4---37537839278.pdf
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b739289c093---76211993295.pdf
    • https://ajwatravel.com/wheelmarine/userfiles/file/mitosavi.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=how+to+make+text+box+expand+in+pdf+form
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000db0a.bin
90bdb5e7a38ef05727f6d53b9c959e2f2ad2e363fee82069872164acd6c86277
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB0A 10856 bytes
font_01_sfnt_off0000f3dd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3DD 16792 bytes
font_02_sfnt_off00010bef.bin
2e14909d697e25864eea9745acb6c2eb8c1870e843bd7e3dabf4a452723cf75a
pdf-font-stream PDF embedded font (sfnt) at offset 0x10BEF 17300 bytes