Malicious PDF — malware analysis report

Static analysis result for SHA-256 bbd5421061278670…

MALICIOUS

PDF

70.0 KB Created: 2021-09-30 17:46:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: f4bbe372f7d0445b795675b0748999a3 SHA-1: 4ae3eb78441c3adde2aab32d79c8dfc674c2bd5d SHA-256: bbd54210612786702fd369ee73efa50bd5ea0e5c1b5ed80f83a1fad4772be885
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests it functions as a link farm, directing users to numerous distinct and potentially disposable domains. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the link farm heuristic point towards a phishing or malware distribution scheme, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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 http://sapientgenerator.ru/files/userfiles/files/dulazexatagivigubojujuked.pdf In PDF document text
    • http://latiendasegura.com/contable_prueba/userfiles/file/rajeduvexi.pdfIn PDF document text
    • http://srmtteaparty.com/uploads/files/202109131907432465.pdfIn PDF document text
    • http://kowel.com/ckfinder/userfiles/files/1631925395.pdfIn PDF document text
    • http://2990592.ru/ckfinder/userfiles/files/50368772269.pdfIn PDF document text
    • http://kasaitogo.com/uploads/files/67871719488.pdfIn PDF document text
    • http://ilyxrace.com/userfiles/files/21307448842.pdfIn PDF document text
    • http://getampedmag.com/ckfinder/userfiles/files/nazaxisalurutoze.pdfIn PDF document text
    • http://ever0036.com/assets/uploads/ckedit/files/20210907091708.pdfIn PDF document text
    • http://dentalweek.eu/userfiles/files/54443864477.pdfIn PDF document text
    • http://munnarteabungalows.com/userfiles/file/xipelijatili.pdfIn PDF document text
    • http://easyliveconstruction.com/ci/userfiles/files/tobupufuzolugu.pdfIn PDF document text
    • http://bronia.org/userfiles/file/44776480219.pdfIn PDF document text
    • http://b40555.handyfriendship.com/upload/files/wusenumodixepekuw.pdfIn PDF document text
    • http://quantri.thaisonpalacehotel.com/upload/files/jodekemeruboki.pdfIn PDF document text
    • https://pakianco.ir/data/image/uploads/news/files/zupopinopes.pdfIn PDF document text
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/4n1vngohdm91li13kpjc6fce4gc6c583/dutunewibokok.pdfIn PDF document text
    • http://sasolution.kr/userfiles/file/24438889827.pdfIn PDF document text
    • http://hzbmsj.net/images/upload/File/sadaxoluvajelaginiregadeb.pdfIn PDF document text
    • http://back2wood.de/userfiles/file/72921159201.pdfIn PDF document text
    • https://galaxytraining.examinationonline.com/files/69914829629.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=telugu+latest+movies+online+streamingPDF 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_off0000afa7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFA7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c7be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7BE 10580 bytes
SHA-256: c053d6f7f20b8946a12b9d982245dfac9940293b8a57e205979772e404fac28c
font_02_sfnt_off0000dfe4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFE4 16572 bytes
SHA-256: 221138eeb60545becce538b106dfbb78ba7b2d0e6217491c8f2f24caeecbefc7