Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb6efe07cd46f6d8…

MALICIOUS

PDF

79.7 KB Created: 2021-09-07 14:46:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 3114fa1fe1dc19576a5669312208c615 SHA-1: d6e34c7fb38280c5f9d8f7832302c455e0497be2 SHA-256: cb6efe07cd46f6d8dae08eef6550d1e001a45b81b320754c27497926c1f03572
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs that form a link farm, with many pointing to compromised CMS upload directories. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for these links, suggesting an attempt to manipulate search engine results or redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://infrive.ru/uplcv?utm_term=hoover+windtunnel+bagless+vacuum+manual PDF link annotation
    • https://lee-trading.tw/archive/upload/files/xejase.pdfIn PDF document text
    • http://udaybharat.in/ckfinder/userfiles/files/33586931765.pdfIn PDF document text
    • http://worldcar.jp/userfiles/files/tabogowarobolobadose.pdfIn PDF document text
    • http://kiiga.ru/userfiles/file/28342937152.pdfIn PDF document text
    • http://johndanton.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/durupibufififulom.pdfIn PDF document text
    • http://m2m2design.com/userfiles/78300864955.pdfIn PDF document text
    • http://goldartline.ua/userfiles/file/tutowired.pdfIn PDF document text
    • http://newbusan.net/FileData/ckfinder/files/20210724_7955902D1BD10BFA.pdfIn PDF document text
    • https://vv-alc.nl/uploads/files/dedezokuv.pdfIn PDF document text
    • https://trongtrucsolution.com/uploads/files/nebowegiliwaxuwisapi.pdfIn PDF document text
    • http://fpole.ru/sadm_files/gekubemufowaxawepovivikig.pdfIn PDF document text
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/be1b09c5ebc89428093628b12655a7fb/wenisirepajetukigunopuxo.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606fcdac6565d---18278881240.pdfIn PDF document text
    • http://dinhvi5s.com/images/newtech/files/posabizodiwo.pdfIn PDF document text
    • https://evergreencans.com/userfiles/file/zozuba.pdfIn PDF document text
    • https://butchercurnow.com/img/shop//contents/mejeje.pdfIn PDF document text
    • http://dayuntang.com/assets/uploads/ckedit/files/20210811081036.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc66be0785---fewolexob.pdfIn PDF document text
    • https://businessservicesuk.com/userfiles/file/jigozej.pdfIn PDF document text
    • https://rebel-guitars.com/wp-content/plugins/super-forms/uploads/php/files/6f0ffeeb0e96fd97f38c971f57439de0/66895669910.pdfIn PDF document text
    • http://chukguwang.com/files/fckeditor/file/47907153362.pdfIn PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/16086918281037---tapazizuvipewawido.pdfIn PDF document text
    • https://hostingyuvasi.com/calisma2/files/uploads/zuvofaxetojuzewo.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/9554fab99bf9993eae633df1e67ef5e7/pokuzobatifikowenuvaved.pdfIn PDF document text
    • http://gorisum.net/fckeditor/upload_file/file/kitapesoluku.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/uscuja5lrq7unjd20if23q5eja/parasokigewebegu.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_off0000cd8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD8A 19068 bytes
SHA-256: df1cbec013efb68f8b00134c06cac41a899428a340b72e94dfece01528fda8b4
font_01_sfnt_off0000ff24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF24 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001173b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1173B 11096 bytes
SHA-256: 9d8b191077315f5f5f7db266995dcfcdbf5cb8da1019e809c2fcefaafa6d9520