Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4df386c916a51fc…

MALICIOUS

PDF

98.0 KB Created: 2021-09-03 10:54:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4b709563acc40942f5ea0733942c8af1 SHA-1: 170816969f321b45f16401e8cfc89647ea430cd5 SHA-256: a4df386c916a51fc7ca6b6b97113e2e6d04411774aa08c5ac2d8585fe9bec95f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan'. The file contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting it functions as a link farm designed to redirect users to malicious content. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9928

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://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/33659924bf754cd3fc6fd6124d9e3a48/timofud.pdf In PDF document text
    • https://vico-real-estate.com/ckfinder/userfiles/files/sizopazozipiso.pdfIn PDF document text
    • http://www.makattakasinti.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074d20fc36bb---2671337905.pdfIn PDF document text
    • http://ekolojikweb.net/upld/userfiles/file/nojikige.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/3d60bfe89fad3a7d58507b1413ddedf7/74313099462.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160734085cea33---40051461136.pdfIn PDF document text
    • https://pinyardim.com/calisma2/files/uploads/siligesavunezuwawadufutu.pdfIn PDF document text
    • https://festivalecolo.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609e026d3e655---tezotikotufagogaxa.pdfIn PDF document text
    • http://clarkstownhs64.com/clients/2/25/255c49a504cbad61718694d8b78dfcdd/File/20252119293.pdfIn PDF document text
    • https://nestsearch.in/admin/uploads/file/fajexepifexudawoliwope.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16088f0fac6878---wemava.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/f8efb868455ef6830184427c4ae8d19d/91784260716.pdfIn PDF document text
    • https://rebel-guitars.com/wp-content/plugins/super-forms/uploads/php/files/f13e0d3b34a58c96c617b4c4abc6a606/sexikukaletatefi.pdfIn PDF document text
    • http://china-hold.com/UploadFile/file/20210805224731333.pdfIn PDF document text
    • http://prime42.ru/userfiles/files/rosovujivoguzesi.pdfIn PDF document text
    • http://payassistinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160790f73af1df---93929512072.pdfIn PDF document text
    • http://montazerangroup.com/uploader/file/42032994780.pdfIn PDF document text
    • https://cedarcreeksauce.com/wp-content/plugins/super-forms/uploads/php/files/86cc68f421feb3164aa7632d24b465e4/senako.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d441fc19967---19711140952.pdfIn PDF document text
    • https://svltv.in/userfiles/files/51609783191.pdfIn PDF document text
    • http://kibunajcc.com/ckfinder/userfiles/files/gozewabim.pdfIn PDF document text
    • https://floraplant.gr/FCKeditor/userimages/file/fisew.pdfIn PDF document text
    • http://mhfmjournal.com/data/22/2/55/64/2544879/user/2788947/htdocs/userfiles/file/nevovejoxinemozas.pdfIn PDF document text
    • http://southfieldhigh1973.com/clients/2/27/27a5067865c8334ad4a5a1fd7642c928/File/fugokofiken.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=apocalypse+of+esdras+pdfPDF 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_off00011ad2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AD2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000132e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132E4 18340 bytes
SHA-256: 510303cbf93b64399355c29822b19566d01de725eb284a810387979b2902d991
font_02_sfnt_off000162f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x162F6 10416 bytes
SHA-256: b8a3bfc6810bb84f6d2a21716c259717cc830add94d586ec92370caa7ca2094e