Malicious PDF — malware analysis report

Static analysis result for SHA-256 36b3851f1c4ee7fd…

MALICIOUS

PDF

85.4 KB Created: 2021-09-19 14:53:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: c3cb3e01235d72549bcbc785a959fba0 SHA-1: cf8fa6eb3993b16e987173eb8b1500083d6e9e62 SHA-256: 36b3851f1c4ee7fd7cacdb547cd8c071ddff8519b647e6d567745d885695675c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics as a link farm, with many URLs pointing to potentially compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The document body is heavily obfuscated and does not provide direct clues, but the presence of numerous external links is the primary indicator of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://agermag.ro/mm/file/85873645902.pdf In PDF document text
    • http://marasintl.com/public/ckfinderuploads/files/44242494621.pdfIn PDF document text
    • http://videocycling.info/files/file/wizubedodiwowotiv.pdfIn PDF document text
    • http://phuclocvienjsc.com/uploads/image/files/24186961401.pdfIn PDF document text
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/161423525254ce---9339029851.pdfIn PDF document text
    • http://ros.by/ckfinder/userfiles/files/97861022947.pdfIn PDF document text
    • https://pomtco.com/technical/files/file/17262493184.pdfIn PDF document text
    • http://speednewslive24.com/assets/ckfinder/core/connector/php/uploads/files/51210836834.pdfIn PDF document text
    • http://phutungvespaco.com/luutru/files/39107461374.pdfIn PDF document text
    • https://phu-komplex.pl/pliki/file/3758001016.pdfIn PDF document text
    • http://www.ekoforte.com/upload/file/zujujag.pdfIn PDF document text
    • https://eghamatsafar.ir/basefile/eghamatsafar/files/44351037642.pdfIn PDF document text
    • http://emiem.pl/public/upload/ckfinder/userfiles/files/witesimujojedaso.pdfIn PDF document text
    • http://watch62.ru/files/files/digosibubugomopezudotafa.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613661b715d9b---kipubefosetodejetevukusiw.pdfIn PDF document text
    • https://energiadirect.pl/application/resources/ckfinder/userfiles/files/kufedexoregupeja.pdfIn PDF document text
    • https://intersat.lv/files/file/19062145896.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/161373822129f3---22117505576.pdfIn PDF document text
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/0781183cde7f040052549681579451df/lorelemutarilaponomelanuk.pdfIn PDF document text
    • https://protraderin.com/userfiles/file/97711870729.pdfIn PDF document text
    • https://triangle-electronics.com/assets/userfiles/file/sirasetetu.pdfIn PDF document text
    • http://toyotarent.kr/FileData/ckfinder/files/20210914_FD34534E3A75E634.pdfIn PDF document text
    • https://nhaccugiare24h.com/uploads/userfiles/file/59356381937.pdfIn PDF document text
    • http://chono.mn/uploads/userfiles/files/modotixikiropimekeduvo.pdfIn PDF document text
    • http://cbgnfinance.com/userfiles/file/xosixezuxu.pdfIn PDF document text
    • https://laatjehuisweerstralen.nl/upload/file/gazebilivizopeduzase.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=best+hacking+os+for+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_off0000ea28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA28 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001023f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1023F 10852 bytes
SHA-256: a27f44c3144df21708c5f623cbb9a3549991fdfc4d7e5881a74907fd85d91092
font_02_sfnt_off00011b1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B1A 17108 bytes
SHA-256: f9136a981de6e0364ea0c9191afe68b206994b20dbb59a20ac8e7d9aa60517ae