Malicious PDF — malware analysis report

Static analysis result for SHA-256 56d1c6b277acdebe…

MALICIOUS

PDF

77.8 KB Created: 2021-09-12 16:35:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: c00a21a986ed367480e007df05c75b16 SHA-1: 338c6c5d845a0b4b42e24f8bbe984581c867e733 SHA-256: 56d1c6b277acdebe153fedcbc33459ce9675bbd308e1c13e98243fa778630d4c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to external websites, 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 phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it's designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9901

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://ketchas.ru/uplcv?utm_term=forgetting+sarah+marshall+streaming PDF link annotation
    • https://gilbertems.com/videos/file/87414810646.pdfIn PDF document text
    • https://istruttorecinofilo.it/userfiles/file/nepalepisegaram.pdfIn PDF document text
    • https://www.auto-ecole-rive-droite.fr/ckfinder/userfiles/files/dirimuradoximaginid.pdfIn PDF document text
    • http://hamyarsanatco.com/ckfinder/userfiles/files/8793220888.pdfIn PDF document text
    • http://scandirent-new.ru/uploads/assets/file/87962922240.pdfIn PDF document text
    • http://sb-78.ru/files/file/podamifix.pdfIn PDF document text
    • http://primaria-ciocirlia.ro/media/file/35262251664.pdfIn PDF document text
    • http://99hospitalitygroup.com/ckfinder/userfiles/files/dujusimarovusibusanisu.pdfIn PDF document text
    • http://cosmikkino.ru/sadm_files/23690116350.pdfIn PDF document text
    • http://monteconsultants.com/image/upload/File/23908583339.pdfIn PDF document text
    • http://yasairamenbar.com/uploads/files/werubijuliralenezoxeg.pdfIn PDF document text
    • https://xehowo24h.com/images/ckeditor/files/lofipisavuwirijukel.pdfIn PDF document text
    • http://lnaixi.com/userfiles/file/20210909073828_6496241.pdfIn PDF document text
    • http://chingyi.tw/userfiles/files/66439912045.pdfIn PDF document text
    • http://slmj8.com/data/userfiles/files/pavomipipinaje.pdfIn PDF document text
    • http://kasand.com/userfiles/97824523131.pdfIn PDF document text
    • https://immo-cjeanpaul.lu/userfiles/files/13733332003.pdfIn PDF document text
    • http://youzedu.com/ckimages/files/20210904034654529620.pdfIn PDF document text
    • http://abwmarlboropike.com/uploads/files/kotovumukovusawoweduma.pdfIn PDF document text
    • http://ros.by/ckfinder/userfiles/files/nefarujupemaguvew.pdfIn PDF document text
    • https://willes-gb.com/uploads/files/202109011517077135.pdfIn PDF document text
    • http://jycjqj.com/uploadfile/file///2021090717112462.pdfIn PDF document text
    • http://csc0311.com/userfiles/file/20210901203415_lwgsyf.pdfIn PDF document text
    • http://aceonlinementors.com/userfiles/file/91993401335.pdfIn PDF document text
    • http://carbontuning.ru/file/73997696759.pdfIn PDF document text
    • http://zhatuogz.com/uploadfile/file/42779201529.pdfIn PDF document text
    • https://maintogelonline2.org/contents/files/88078555418.pdfIn PDF document text
    • http://year-c.com/upload_fck/file/2021-9-6/20210906095250290219.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_off0000cb2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB2E 10532 bytes
SHA-256: e0f3dddd69e0fde07a0c7a85d6c90b905ae101822e2d7413e9f022573318848c
font_01_sfnt_off0000e2f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2F6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fb08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB08 17708 bytes
SHA-256: 136191c9b7d0a7b79097cdebb54a4cb5ea6f368429126f71bf59bebeaacf76f4