Malicious PDF — malware analysis report

Static analysis result for SHA-256 789081837bcb321c…

MALICIOUS

PDF

78.2 KB Created: 2021-09-20 19:30:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 5822131a03f022b5e42d24140ded021d SHA-1: 8375194ab3fd151865bf6de917146341ed32620e SHA-256: 789081837bcb321c4b2b583da03f3979043e18b04232f10f82d5ecdd6fecb15e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics as malicious, including a high ML score and ClamAV detection. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users to potentially harmful content. The presence of these link farms suggests an attempt to distribute malware or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 https://crysiq.ru/uplcv?utm_term=computer+keyboard+app+for+android+mobile PDF link annotation
    • http://ozdoby-betonowe21.pl/Upload/file/zevixusoturogi.pdfIn PDF document text
    • https://wfbulgaria.com/uploads/wysiwyg/files/70569280628.pdfIn PDF document text
    • https://www.prshots.com/ckfinder/userfiles/files/92473616686.pdfIn PDF document text
    • http://apartamentykunickiego.pl/architekci/public/upload/ckfinder/userfiles/files/zoguzotusefulamotewude.pdfIn PDF document text
    • https://ww150004.linebot.net/upfile/files/20210916091202.pdfIn PDF document text
    • https://espritgt.com/userfiles/file/27660237007.pdfIn PDF document text
    • https://cqhuaan.myhost360.cn/upload/files/09-03-04-15-01-97.pdfIn PDF document text
    • https://fertilizergranulatorprice.com/d/files/dobogujisejifadore.pdfIn PDF document text
    • http://asacnfservices.com/ckfinder/userfiles/files/51691374622.pdfIn PDF document text
    • http://tt-ural.su/admin/ckfinder/userfiles/files/savixozumavazivine.pdfIn PDF document text
    • https://sharedsynergy.com/userfiles/file/karitixij.pdfIn PDF document text
    • http://anabakorea.jp/userfiles/file/11395439165.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/xelez.pdfIn PDF document text
    • https://efficimm.fr/userfiles/files/duwodumotuxapirap.pdfIn PDF document text
    • https://dubigroup.com/admin/fckeditor/editor/filemanager/connectors/upload/file/92164160300.pdfIn PDF document text
    • https://blugarden.eu/file/62488706948.pdfIn PDF document text
    • http://machinesupplier.cn/data/product/file/202199_53045_692.pdfIn PDF document text
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130d06917faa---dedikebenenoxitegumak.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136a929c0e95---majexugurovujasi.pdfIn PDF document text
    • https://trainova.com/userfiles/file/visopojalanevizupelodatok.pdfIn PDF document text
    • http://cyclad.org/UserFiles/file/48609998479.pdfIn PDF document text
    • https://novitas.ro/files/zaduno.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/161428ce41ea9f---zofifefewanato.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_off0000cc58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC58 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e46a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE46A 17368 bytes
SHA-256: e2749deda585d385f890f815a60ea93362c7d141a99e4bf8e1a461dbe636b2fe
font_02_sfnt_off000111ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111AE 10968 bytes
SHA-256: 780c8e5d04900194c6f5f0fede7cf8d3ea7febce33589876644ff134f61e7707