Malicious PDF — malware analysis report

Static analysis result for SHA-256 818a518e8efc4841…

MALICIOUS

PDF

84.1 KB Created: 2021-09-13 14:44:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: ccc3b352cfb4a55e4a5c85ebc1c0500a SHA-1: 644b62194b8e62d64f7de68cf994ad99ae7811be SHA-256: 818a518e8efc48412dbedfd62a9d84441c0272a8b080a47d171f8fdc2a548163
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://irlanc.ru/uplcv?utm_term=real+cricket+3d+game PDF link annotation
    • https://pmsp-me.com/userfiles/files/25180689597.pdfIn PDF document text
    • http://tc-antey.ru/uploads/files/dovonavofawevekokesegobu.pdfIn PDF document text
    • http://finadev-groupe.com/userfiles/file/34300942411.pdfIn PDF document text
    • http://caphegiabao.com/upload/fck/file/82781607442.pdfIn PDF document text
    • http://signauction.net/userfiles/file/67720352619.pdfIn PDF document text
    • http://nordicwalkingturak.hu/_user/file/151924548.pdfIn PDF document text
    • http://bsp-oblspl.org/ckfinder/userfiles/files/45031148434.pdfIn PDF document text
    • http://clear-es.net/yamituki-n/uploads/files/nufedezaw.pdfIn PDF document text
    • http://gmei.lt/ckfinder/userfiles/files/54825920946.pdfIn PDF document text
    • https://euforbiabulgaria.com/uploads/pages/files/zenivivat.pdfIn PDF document text
    • https://hoangvan.vn/wp-content/uploads/files/wuvixujagewijotatika.pdfIn PDF document text
    • https://mekongtransport.com/upload/userfiles/files/pizijijuduvisixuko.pdfIn PDF document text
    • http://sensor4you.com/fckeditor/editor/filemanager/connectors/php/fckeditor/upload/202109/file/kifoxovil.pdfIn PDF document text
    • https://wintechindia.in/ckfinder/userfiles/files/27004746953.pdfIn PDF document text
    • http://artdealer.vn/upload/fckimagesfile/05896b3ccba77e0fe42967d106a4a5a2.pdfIn PDF document text
    • http://gysanya.com/upload/file/210911231246861662j8upur1kylxf.pdfIn PDF document text
    • http://2016.letnifestiwal.pl/ckfinder/userfiles/files/27080294290.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1613dab5629a8d---92516269177.pdfIn PDF document text
    • http://thriftstorewebsites.net/flash/thriftstorewebsites.net/file/guperamaxowotanobinisuzi.pdfIn PDF document text
    • https://motodubai.com/uploaded_images/files/mejopigesopo.pdfIn PDF document text
    • http://baove24h.org/upload/files/gukowuvewo.pdfIn PDF document text
    • https://xn--fct5g39pjpo.tw/upload/leakstop/files/juvedigarogage.pdfIn PDF document text
    • http://studiomilano.eu/userfiles/files/48954233183.pdfIn PDF document text
    • http://wojno-stal.pl/pliki/file/7084756551.pdfIn PDF document text
    • http://sarljarry.fr/userfiles/file/kerukexekoserobaxovo.pdfIn PDF document text
    • https://evrenmentese.com/upload/ckfinder/files/3431654519.pdfIn PDF document text
    • https://marblobathware.com/app/webroot/img/files/muvulu.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_off0000e2ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2EC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fafe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAFE 18412 bytes
SHA-256: 54a52f19e1eea08bc56bddd0dd6860ee8912b73de3913ce59b94140165785f07
font_02_sfnt_off00012a90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A90 10628 bytes
SHA-256: b8bcaf6de5887efd3d291bb6a611d8d84fadb0761668faefb748c343bd3ea7b2