Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd83bee31558f00e…

MALICIOUS

PDF

91.7 KB Created: 2021-09-14 18:19:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 0cd4d03fae530f7133eda102d36f0efb SHA-1: 63aa9f5fef15f8ce73cf456748bd41c9d760fa4e SHA-256: cd83bee31558f00e3460d6020e49faaa3a05995a21845fe71dfe626d6e82f891
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a large number of embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed for malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9930

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 http://zenithmetals.com/files/63466510694.pdf In PDF document text
    • http://hacoauto.vn/upload/files/18608290082.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16135df6e002ac---84146293366.pdfIn PDF document text
    • http://www.chiringuitomediterraneo.com/ckfinder/userfiles/files/22891603311.pdfIn PDF document text
    • http://vrajacreation.com/uploaded_files/userfiles/files/16684770612.pdfIn PDF document text
    • https://colegiumaniucarei.ro/ckfinder/userfiles/files/pekata.pdfIn PDF document text
    • http://a2kat.ru/userfiles/file/42897544126.pdfIn PDF document text
    • https://paeonia.ch/userfiles/files/wevik.pdfIn PDF document text
    • https://korzayithalat.com/spot/admin/fckeditor/userfiles/file/96444031989.pdfIn PDF document text
    • http://aa-nusd.jp/mapisuwiparadaxexozovip.pdfIn PDF document text
    • https://pataniforum.com/admin/jquery/ckfinder/userfiles/files/32481976510.pdfIn PDF document text
    • http://evolution-dev.com/file_media/file_image/file/babupavud.pdfIn PDF document text
    • http://express-service-auto.fr/ckeditor/ckfinder/userfiles/files/kopimosiwa.pdfIn PDF document text
    • http://dongphat.net/upload/files/botaba.pdfIn PDF document text
    • http://gyndoktors.de/ckfinder/userfiles/files/pigud.pdfIn PDF document text
    • https://dm288.rs/slicice/file/49161331583.pdfIn PDF document text
    • https://implantsdentairesdesmoulins.com/upload/editor/file/66877214601.pdfIn PDF document text
    • http://confidenzacsapagy.hu/upload/viranog.pdfIn PDF document text
    • https://cbconsulting112.ca/userfiles/files/losulobe.pdfIn PDF document text
    • http://studiomontironi.eu/userfiles/files/27764236926.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/85e19508224749ff9b34b2ddc1270bad/nitumefopikixiwagezi.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/fd6487c6381d9e732debcb5fd3799d9e/viseguwevebunamugaga.pdfIn PDF document text
    • https://baxsporthorses.nl/userfiles/file/rixabagumegurofelonok.pdfIn PDF document text
    • http://anneadamslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/19870041289.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=60+seconds+apk+2021PDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e8ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8FF 10628 bytes
SHA-256: 1bd63b30bca71b8dcb5208f37a309518ab0efab0ae001783f81c04a6c2bcd896
font_01_sfnt_off00010179.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10179 24824 bytes
SHA-256: 1af42a486776a8a2d0c93334e15ff269eb0db4224127e056acbf1bc1655df292
font_02_sfnt_off00013f2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F2D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off0001573a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1573A 1680 bytes
SHA-256: 6c08887b596ecb472c5a0482df8c2f828d83fc5b5d16111ed0caa1fced1b35dc