Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb59fa18ba5c9370…

MALICIOUS

PDF

81.7 KB Created: 2021-09-16 00:33:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: d7e33b084f832dda16ae4606f17de069 SHA-1: cf7960760ae1088f04402fc076bb438532e33fe8 SHA-256: bb59fa18ba5c93709dcf33938f0e19472c14bd60c78d82a7d97c040482950472
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm. It contains numerous embedded URLs pointing to external PDF files hosted on various domains, suggesting an attempt to redirect users to potentially malicious content or phishing sites. The PDF structure and embedded content are indicative of a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://naphotelbangkok.com/userfiles/files/56030108686.pdf In PDF document text
    • http://khocabien.com/uploads/files/nukazokifakatoxamukotome.pdfIn PDF document text
    • http://hcm-invoice.vn/hinhanh_fckeditor/file/wozake.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/8f89f213ede9342ab93d85dea41392e2/95067242487.pdfIn PDF document text
    • http://www.iuoelocal870.com/kaizen/ckfinder/userfiles/files/xezifirokaritajuted.pdfIn PDF document text
    • http://vinaktv.com/storage/ckfinder/files/xuturozatexulogunu.pdfIn PDF document text
    • http://boldogelet.hu/media/84779453013.pdfIn PDF document text
    • https://y3stwk65l-mn9.com/contents/files/serarimamudojuposene.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132d472c3672---54259631707.pdfIn PDF document text
    • http://nexxosrealty.com/userfiles/files/59889026339.pdfIn PDF document text
    • http://bwemfjhjk.friend-match.com/upload/files/kixufezuwased.pdfIn PDF document text
    • http://artikos.pl/userfiles/file/xegutu.pdfIn PDF document text
    • http://www.fan-consultants.com.tw/ezadmin/ckfinder/userfiles/files/ranigaretanesakizele.pdfIn PDF document text
    • http://thcscatquea.hoaiduc.edu.vn/ckfinder/userfiles/files/suxifu.pdfIn PDF document text
    • https://coebmsf.com/userfiles/file/39012426754.pdfIn PDF document text
    • http://globalfeedindustry.com/upload/files/tetozebu.pdfIn PDF document text
    • https://hotel-la-licorne.fr/userfiles/file/mifanozudakurojiradabo.pdfIn PDF document text
    • http://printific.com/images/contentimages/files/8388057607.pdfIn PDF document text
    • http://proficlim.ru/public/userfiles/file/61390086843.pdfIn PDF document text
    • http://yuhao-tech.com/userfiles/file/19143786247.pdfIn PDF document text
    • https://hearing-outlet.com/uploads/files/202109070654141851.pdfIn PDF document text
    • https://ibeguiristain.com/userfiles/files/99303846359.pdfIn PDF document text
    • https://kampusogrenciyurdu.com/file/toluke.pdfIn PDF document text
    • https://ww150002.linebot.net/upfile/files/20210904225930.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=red+eye+looksPDF 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_off0000df0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF0A 9936 bytes
SHA-256: c6d5a0c2926f974f0d34cd035ef80cb375e0c8fbba1ca754c9b6aaeace9ef38f
font_01_sfnt_off0000f526.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF526 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010d38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D38 17004 bytes
SHA-256: 8c8b9098834813308289fd763a89238a9e74e7a411c8074a919a2677bd8aeede