Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fff1790f3eef542…

MALICIOUS

PDF

68.7 KB Created: 2021-10-02 23:45:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 6eaaa0bc92e347ddba4db3b4b6cfc4b3 SHA-1: 00354c0dbd067b8cdb364a88d2dc4fa74eb76a3d SHA-256: 8fff1790f3eef542fc874d7272c4a5680ad0cb3f83932bc4ea37669e8a4b0ab3
156 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised CMS uploads and disposable hosting, indicating a link farm designed for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. The file's structure and numerous external links align with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://dreamsurgeryen.net/ckupload/files/4594163542.pdf In PDF document text
    • http://billsky.ee/files/file/bajabadat.pdfIn PDF document text
    • https://globalcircle.club/userfiles/file/53608960588.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/161586406afd23---7780344345.pdfIn PDF document text
    • http://373113.linker.tw/files/rejaxovekat.pdfIn PDF document text
    • http://olynskiconstruction.com/pics/file/13564979735.pdfIn PDF document text
    • https://bimstudioinc.com/media/files/lokirif.pdfIn PDF document text
    • http://revize-elektro.info/UserFiles/File/soriwu.pdfIn PDF document text
    • http://contelex.it/userfiles/files/18483983433.pdfIn PDF document text
    • http://xn--knstlerische-biografie-arbeit-lbd.ch/userfiles/files/74812501220.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137678e59947---ralodupavuwesamat.pdfIn PDF document text
    • http://choragwica.pl/userfiles/file/livafuwebopix.pdfIn PDF document text
    • http://nakajima-ya.com/upload/save_image/files/badaladixawa.pdfIn PDF document text
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/5b0eaca6c08cc034b6838658028ba0e5/mefoj.pdfIn PDF document text
    • https://bio86.net/userfiles/fichiers/20551222497.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/74607965327.pdfIn PDF document text
    • https://mai-avto.ru/upload_files/file/xawifulof.pdfIn PDF document text
    • http://soeurs-scjboran.fr/soeurs/upload/files/3578788838.pdfIn PDF document text
    • https://ptkas.com/kingkong/userfiles/files/pegojufunojedosarunafaga.pdfIn PDF document text
    • http://aktasmatbaacilik.com/resimlerfiles/35029316296.pdfIn PDF document text
    • http://lauraestetica.com/userfiles/files/66427529438.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=thank+you+for+being+godPDF 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_off0000aed6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAED6 15032 bytes
SHA-256: 5b7c2e35fe13246c405b307bd40b7d7a91ebf9e9ac780bdafb32cc0519490423
font_01_sfnt_off0000d4bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ecd6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECD6 10728 bytes
SHA-256: 872bbd6f27e6edc8c9246c33fd8dbf4a7f57df900a1b364ccdfb375c5597952a