Malicious PDF — malware analysis report

Static analysis result for SHA-256 666630f185ee7640…

MALICIOUS

PDF

100.9 KB Created: 2021-06-29 02:52:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5c61fb0207e9ef0c779b209b1c95664f SHA-1: ca5f407b60e32350cb076d93503b8b9ed28c9019 SHA-256: 666630f185ee76407c517bb5f0352c7d9dabcdb8b005f9d5165b0b0cabfd1bc1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF functions as a link farm, directing users to multiple compromised WordPress sites and disposable hosting domains. The embedded URLs and the nature of the heuristics suggest the primary goal is to redirect users to potentially malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9888

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://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/00999717bcbe42aebc839438f6a027e3/89122190855.pdf
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f02250e50c---zalevutililiju.pdf
    • http://xn----9sbbnbtte4cyg.xn--p1ai/ckfinder/userfiles/files/11746659771.pdf
    • http://1utilaje.ro/mm/file/56460977455.pdf
    • https://alice-immo.com/userfiles/file/59923481916.pdf
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083a6417df29---4800123791.pdf
    • https://kurtoglumob.com/upload/file/97111830392.pdf
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/dab6f0790381748a4ca6eb982835d8d2/nerewepodosobumonovem.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607bacf078ca9---zefuzekezetorilasupewabup.pdf
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c6ff7c4c56a---pegokivudenujo.pdf
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607aa908380bc---61832018927.pdf
    • http://aksaaydinlatma.com/img/editor/image/file/27022849443.pdf
    • http://kyanite.tv/userfiles/file/dodakumedawuwodojujafudo.pdf
    • https://daluxerealty.com/wp-content/plugins/super-forms/uploads/php/files/f293tbne8rou75mcnn45h9pr97/resukezabakawumesulem.pdf
    • http://geostudio.eu/userfiles/files/81882155102.pdf
    • http://esistore.de/userfiles/file/31901008940.pdf
    • http://sashtraayurveda.com/ckfinder/userfiles/files/kibamisoxisonalek.pdf
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/v1hb3afo5lo7qiu1150jj597p3/81968119643.pdf
    • http://project-st.ru/userfiles/file/53444610555.pdf
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/834156beb8247ade9e3ac700a0aa892f/22736986010.pdf
    • https://healthcareadvisorsgroup.com/wp-content/plugins/super-forms/uploads/php/files/ohpnvopuekoh2u0namknd4ojk5/palepamikidurenezezulo.pdf
    • https://puppometalli.eu/file/dipuman.pdf
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba18ed04961---39315256754.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=funny+ask+fm+answers
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001120b.bin
0b3c92812a73e26af128ca6e5cd59003cc79b2291176eaf9606e0dffc4e90f75
pdf-font-stream PDF embedded font (sfnt) at offset 0x1120B 17564 bytes
font_01_sfnt_off00014025.bin
ef858b01719cec29ba59f81a977f79613a1aab7fbc1f32c2ef09c5dd0d876d7f
pdf-font-stream PDF embedded font (sfnt) at offset 0x14025 16276 bytes
font_02_sfnt_off00015622.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x15622 16792 bytes
font_03_sfnt_off00016e39.bin
e9a9999110d75f9cefcdf0d6b45783f59e8d28f57391d2ec1a64cd4b332000ad
pdf-font-stream PDF embedded font (sfnt) at offset 0x16E39 10388 bytes