Malicious PDF — malware analysis report

Static analysis result for SHA-256 4840ad8283317d3f…

MALICIOUS

PDF

79.7 KB Created: 2021-09-17 11:07:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 12977d6c2476daafe89cacc5be230f1f SHA-1: 235a45e3e3d2995cf29239807f714e8f38286272 SHA-256: 4840ad8283317d3f02ba55ae580a30b059d35c894f6d531e4e7d3cac632be55d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed for malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the structure and URL patterns are indicative of a malicious document, potentially delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://coretry.ru/uplcv?utm_term=music+video+converter+to+mp4 PDF link annotation
    • https://www.lavishlook.se/wp-content/plugins/super-forms/uploads/php/files/1d57daea08ea35ed7addfad9f99690e9/11847370415.pdfIn PDF document text
    • http://free-note.kr/files/fckeditor/file/347832537614061405544c.pdfIn PDF document text
    • http://kristiankutschera.de/userfiles/file/rumarerixuvofixuwuzamu.pdfIn PDF document text
    • http://nutrizionisti.eu/public/thread/risorse/file/29710539199.pdfIn PDF document text
    • http://nsdadventist.org/FCKData/file/66758740332.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/161426553909f2---tepenusipazopofetuvizuno.pdfIn PDF document text
    • https://calendarsunrooms.com/userfiles/files/23416748035.pdfIn PDF document text
    • http://thuduchouse.vn/pics/file/raretunefo.pdfIn PDF document text
    • https://benmoonpharma.com/userfiles/file/46945916727.pdfIn PDF document text
    • https://spcinternational.in/ckfinder/userfiles/files/13199944812.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/b28bbe6d322019fad1633509e9e846d8/lipavitug.pdfIn PDF document text
    • http://hoaiduc.edu.vn/ckfinder/userfiles/files/pudusepunixedovifaje.pdfIn PDF document text
    • http://www.masozilina.sk/ckfinder/userfiles/files/vofalikejunujuvu.pdfIn PDF document text
    • https://ra7a7p-h3ba7.com/contents/files/65771615942.pdfIn PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/827f30d5038876ffcdcdf7afa8cdb08d/77194341999.pdfIn PDF document text
    • https://tapuionoticias.com/ckfinder/files/gufenogozagawowaj.pdfIn PDF document text
    • http://wskinbody.com/data/boardData/files/11220098635.pdfIn PDF document text
    • http://patronusalapitvany.hu/public_html/upload/36182623365.pdfIn PDF document text
    • http://www.wiz-fac.com/uploadImg/file/54555567333.pdfIn PDF document text
    • http://1hozain.ru/files/userfiles/files/79699883478.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_off0000d1be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1BE 10704 bytes
SHA-256: 9acd8064a7fde6cfe120068a522adf4a0ec1bb277a58968126c1027d94c176a0
font_01_sfnt_off0000ea60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA60 18044 bytes
SHA-256: ffbdeffbb3067931e81d5d850c9b135903368068e00d5b4172e5066d75707765
font_02_sfnt_off00011942.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11942 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1