Malicious PDF — malware analysis report

Static analysis result for SHA-256 b56f9397213cb6b3…

MALICIOUS

PDF

82.9 KB Created: 2021-09-14 12:49:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 4dd2f4c4ba086a2a80d30d4565f6e1ff SHA-1: 79e00cc3e23a6f8b33709d7b9b4ba80dfc2e7b01 SHA-256: b56f9397213cb6b3429acf85b54e9ac140e0654632bc8f5149e174fa5b744679
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm, with many URLs pointing to disposable hosting or compromised CMS upload storage. The embedded URLs suggest an attempt to redirect users to malicious sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://leruichem.com/upload/files/9760497313.pdf In PDF document text
    • http://4reality.cz/userfiles/files/rokivavuzidumoxivoseg.pdfIn PDF document text
    • https://terminal.hr/userfiles/file/23833809525.pdfIn PDF document text
    • https://sledovani2.gpshlidac.cz/www/userfiles/files/jubukamisidubisebaperisep.pdfIn PDF document text
    • http://medical-1669.com/userfiles/files/tibilimif.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/161353ce85205f---23999909228.pdfIn PDF document text
    • http://wsmr.us/userfiles/file/jinapuzufin.pdfIn PDF document text
    • http://ghalemdi.com/userfiles/file/dakozenetageruwibozabol.pdfIn PDF document text
    • https://aneri12.eu/res/file/zatupupotosuroxubote.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/74c9bfadf13fa5858c84abc783744719/20913124915.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131d0202e7f7---69096874537.pdfIn PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/161396a91941ca---juparajuvi.pdfIn PDF document text
    • https://iwistw.com/upload/files/55081627542.pdfIn PDF document text
    • http://roocenter.ru/upload/file/93616190172.pdfIn PDF document text
    • http://tgtech-auto.com/userfiles/file/74964653680.pdfIn PDF document text
    • http://csc-028.com/userfiles/file/20210914082339_n7umvf.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/34727977918.pdfIn PDF document text
    • https://arichaindia.com/userfiles/file/tojusonaru.pdfIn PDF document text
    • http://vietcem.vn/public/default/ckeditor/files/texiwelodunijofobegovugan.pdfIn PDF document text
    • http://uran-berlin.com/userfiles/file/14544331569.pdfIn PDF document text
    • https://sagarexpress.com/userfiles/file/78319428839.pdfIn PDF document text
    • http://longarmquiltacademy.net/fckeditor/userfiles/file/duvavugusarekotez.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d9ae0d4292---98391627473.pdfIn PDF document text
    • http://ubestsports.com/imager/files/20210911084248.pdfIn PDF document text
    • http://kutscher-customs.de/gfx/userfiles/files/dadip.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=sprite+maker+androidPDF 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_off0000d800.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD800 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f012.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF012 20668 bytes
SHA-256: b192009ad6bdeaa19d2527b39ef112e36d55cbfeb5536956d0e9ae44ef43d622
font_02_sfnt_off0001265d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1265D 10508 bytes
SHA-256: 98a0b925f53e48c1877b6a8116ccdb16a3d4a4bab717a9b94d928d3cd67ef919