Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f4b22c042646e00…

MALICIOUS

PDF

85.3 KB Created: 2021-09-18 19:51:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: a2ba065a4b2300d156ea301e5fbe99f4 SHA-1: 6d565604bc2c8f32c6e81070ac3eaf74b2bbe508 SHA-256: 1f4b22c042646e00bc9ddabde6d41ffa0d2c813cc0616f80245d1983bd18811f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF document detected as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to disposable hosting and appear to be part of a link farm designed to redirect users. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically flags this behavior. While no scripts were explicitly extracted, the presence of embedded URLs and the overall structure suggest a phishing or redirection attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://philabc.ru/uplcv?utm_term=sophie+fashionista+dress+up+game+online PDF link annotation
    • https://sherwoodchamber.org/ckfinder/userfiles/files/68973120234.pdfIn PDF document text
    • http://weilandvloeren.nl/fckimages/direrolibatujigefi.pdfIn PDF document text
    • http://tbeaindia.com/userfiles/file/bojawijuvawujomala.pdfIn PDF document text
    • http://szkolaprzybranowo.pl/ckfinder/userfiles/files/mewawixeputup.pdfIn PDF document text
    • http://myphamasia.net/upload/files/zujixifimorojutonavoxi.pdfIn PDF document text
    • https://primer-spb.ru/files/files/77118016581.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16136b8136e654---pozofonobakugan.pdfIn PDF document text
    • http://ediliziaunoaventi.com/userfiles/files/mizimosifewaguwefapewajew.pdfIn PDF document text
    • http://nail-free.com/ckfinder/userfiles/files/16521087414.pdfIn PDF document text
    • http://piotrkowska77.pl/zdjeciafile/59435063842.pdfIn PDF document text
    • http://izhar-energy.com/userfiles/file/bopalebuvadoxezomujozevab.pdfIn PDF document text
    • http://latiendasegura.com/contable_prueba/userfiles/file/gumupikaboxopubukuwujaza.pdfIn PDF document text
    • https://cfaegaianascente.pt/portal/userfiles/files/falugorasidagagavijejivu.pdfIn PDF document text
    • http://ilsungwarehouse.com/userData/ebizro_board/file/55671980243.pdfIn PDF document text
    • https://anna-bel.com/app/webroot/files/userfiles/files/82340100997.pdfIn PDF document text
    • http://www.kevimotor-rock.hu/files/files/67225743001.pdfIn PDF document text
    • https://hawkseyetravels.com/assets/ckfinder/userfiles/files/87222909829.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1614526aeac65a---56790677805.pdfIn PDF document text
    • https://ashleymongolia.mn/uploads/files/98757992733.pdfIn PDF document text
    • http://phunphu.com/userfiles/file/fukivofogup.pdfIn PDF document text
    • http://hbaoge.com/upload/files/numepajesasefa.pdfIn PDF document text
    • https://optical-axis.com/uploads/files/202109131923013743.pdfIn PDF document text
    • http://cambresisemploi.fr/ckfinder/userfiles/files/90234707445.pdfIn PDF document text
    • http://carrasvilla.es/uploads/files/52835754928.pdfIn PDF document text
    • http://gzhangqin.com/uploadfile/files/zalunipidasakorof.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_off0000e488.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE488 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fc9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC9F 11120 bytes
SHA-256: 257be8d7e421dc9793c18c38879d31d68f351fc460a613c0d218d89e7dd2ab44
font_02_sfnt_off0001162c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1162C 19032 bytes
SHA-256: c68663c625efb731ec1eac240a169c96e2bfc1824d0ac5b1abdfd4e9ebdc837d