Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4a8aa4d82b79741…

MALICIOUS

PDF

82.8 KB Created: 2021-09-04 19:54:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 9be82d6c7c2bcdf7107a48632572e960 SHA-1: 7c0cf739d8e9fa7caeb4a3a60ba05f8e2733b158 SHA-256: f4a8aa4d82b797413f0aebf8f908c8119ed262c236cde619667149d3dec60a79
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to numerous distinct hosts, many of which appear to be compromised WordPress sites used for hosting PDF files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. Although no scripts were directly extracted, the PDF structure and embedded URLs suggest it's designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.doctor-carpet.com/wp-content/plugins/super-forms/uploads/php/files/j6iaaq2761ngglu70ea9sbm490/27355421990.pdf In PDF document text
    • https://www.nordatec.com/wp-content/plugins/super-forms/uploads/php/files/hircsffu8bp5j7monhm3o4agos/luvaduxarevunogi.pdfIn PDF document text
    • https://lecourbe.dk/userfiles/file/letiwid.pdfIn PDF document text
    • http://ristoranteyuri2.com/userfiles/file/gipubugav.pdfIn PDF document text
    • https://dhesient.com/media/52836288943.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c73ebe2240a---10701410359.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160804012af15c---jukufevuvikagilif.pdfIn PDF document text
    • https://razdolle.by/wp-content/plugins/super-forms/uploads/php/files/6hft931epgdns0k8eqi1qpcti3/92019078314.pdfIn PDF document text
    • http://accomplishtheimpossible.com/userfiles_ati/file/fisojevudumikajis.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160772d6bde0db---wikoga.pdfIn PDF document text
    • http://okfilm.kr/userData/board/file/bifoxokez.pdfIn PDF document text
    • https://cashmeredreams.com/wp-content/plugins/super-forms/uploads/php/files/0317abf94d549fd868ddef12dc9753dd/besezumejupanu.pdfIn PDF document text
    • http://progfin.pl/userfiles/file/dazajoputoxube.pdfIn PDF document text
    • http://dokumsuzgec.com/userfiles/files/40658079612.pdfIn PDF document text
    • http://k-sta.kr/FileData/ckfinder/files/20210803_91D83E187A165DF4.pdfIn PDF document text
    • http://akkoryazilim.com/userfiles/file/pufalozosenerosaf.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/160f5ab52cba5a---wiromilazexavimomapigus.pdfIn PDF document text
    • http://ddaengshop.com/ckupload/files/bagiditotozafopiwetef.pdfIn PDF document text
    • https://bushregenerators.biz/userfiles/files/seturuzivukopok.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dc180474dca---36477074921.pdfIn PDF document text
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/e0725de2ac80506d5d5773aa6696d2eb/mazimo.pdfIn PDF document text
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/12bg28amcujguvfqa7h01ar3o5/22523419076.pdfIn PDF document text
    • http://laser-piskovani.cz/democms/userfiles/file/28835542170.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f7cb523573e---tizaxulig.pdfIn PDF document text
    • http://commsoft.nu/demo/ktb/wsmbilder/files/sutenisanunukuwufosa.pdfIn PDF document text
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/160bfa3a69e898---firoradupudawebifom.pdfIn PDF document text
    • http://denis-lefebvre-services.com/fichiers/file/98210781262.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=lutron+ms+ops2+occupancy+sensor+switch+manualPDF 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_off0000d83e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD83E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f050.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF050 19580 bytes
SHA-256: 8849fb667e2979bf41b113a6757dbbd05a567cdcb9c29c49ac6ee3b975f69560
font_02_sfnt_off00012360.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12360 11016 bytes
SHA-256: 9e06920159310fb98d5c34c399369d2940494e8b5cb6fb7b6c022b3f98ed904a