Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1b888735221a42c…

MALICIOUS

PDF

68.2 KB Created: 2021-09-30 23:43:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: 2810728bdf17d0fdb6d1ca49db324b06 SHA-1: c5ad18329ccb34290fe41b96ede03a1c9013c130 SHA-256: b1b888735221a42c6043146df6dfd25c64633f174ab359043a58ba9fde45681b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs pointing to a link farm, suggesting a phishing or malware distribution scheme. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags the sample's structure as a link farm on disposable hosting, reinforcing the malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 http://hfnhsw.com/upload/files/meduzikewinorudefotosidam.pdf In PDF document text
    • https://gimenezricarte-deltabogados.com/ckfinder/userfiles/files/20416469490.pdfIn PDF document text
    • http://autoklej.pl/app/webroot/media/files/sezupepasuf.pdfIn PDF document text
    • http://degeninhotel.ru/admin/ckfinder/userfiles/files/mozopolukipofowolasugod.pdfIn PDF document text
    • http://aqua4you.hu/userfiles/file/sixapatapa.pdfIn PDF document text
    • http://nhatrangpalacehotel.com/app/webroot/upload/files/fikowijapulukudivalaj.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/161413aa7afb98---86759005143.pdfIn PDF document text
    • https://hanomanberjaya.com/contents/files/14892942608.pdfIn PDF document text
    • http://mtecommerce.it/public/news/file/72318933904.pdfIn PDF document text
    • http://nt-module.ru/ckfinder/userfiles/files/8587803908.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/su48bddpickmu01edqgja9tho7/30237601533.pdfIn PDF document text
    • http://starroadchina.com/userfiles/file/14056987029.pdfIn PDF document text
    • http://0228339500.kad.tw/kads/ckfinder/userfiles/files/waxekegerederipojatut.pdfIn PDF document text
    • http://anaminfo.com/attachfile/file/91640422894.pdfIn PDF document text
    • http://xn----ftbkdcamitb5h.xn--p1acf/files/fck/file/lelepevejivitenizibu.pdfIn PDF document text
    • http://cualuoiskydoor.com/webroot/img/files/81715076722.pdfIn PDF document text
    • http://studiodugnani.it/userfiles/files/32383344590.pdfIn PDF document text
    • http://tayles.com/uploaded/59016983699.pdfIn PDF document text
    • http://safiorida.nl/operatori/userfiles/file/79273047010.pdfIn PDF document text
    • http://soleilboo.com/images/uploads/files/61997077037.pdfIn PDF document text
    • http://hemeringen.de/ckeditor_ablage/userfiles/files/17154802964.pdfIn PDF document text
    • https://bagstyle.uz/images/file/3994736766.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=life+after+beth+123moviesPDF 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_off0000ab74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAB74 14816 bytes
SHA-256: dba28e94868d4cc59b7b11f99b7ad2eb9c1fca50b11de1514b4d64f05d16cc3c
font_01_sfnt_off0000d0a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0A8 10836 bytes
SHA-256: 3a6b29b8c7af8339d2dbe63326c49af50dca080bcee955fa541f4575c41c027d
font_02_sfnt_off0000e9d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9D8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1