Malicious PDF — malware analysis report

Static analysis result for SHA-256 99c4cd97131cecc4…

MALICIOUS

PDF

86.3 KB Created: 2021-09-05 19:20:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5f4a20e3e31ae0383f386169d84b5baf SHA-1: d49dccaeb4bc792ea080bd9461753d1ebe296a20 SHA-256: 99c4cd97131cecc4d6c19bca5d93838bb5f9bcf1f961eee3651af7975a8efc1d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection for 'Pdf.Phishing.Trojan'. The file contains a link farm pointing to compromised WordPress upload storage and other disposable hosting, suggesting an attempt to redirect users to malicious content. While no scripts were explicitly extracted, the PDF structure and URL patterns are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160a0b4c6162f4---20984127200.pdf
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/1o4vquojhjkoj8f19l4k55rl27/38149760671.pdf
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/ab4d03520227f2815c7339fee1e47e75/vinekepabusiwanum.pdf
    • https://mimpi1pusat.com/contents//files/momunabodoxekaxurugozet.pdf
    • http://hanabi-la.com/uploads/files/89583393557.pdf
    • https://bamor.org/userfiles/file/naremedetogafixewomes.pdf
    • http://csc028.com/userfiles/file/20210731210738_3jg8th.pdf
    • http://cableesmaltado.com/d/files/mufafozite.pdf
    • https://hv2barrier.com/application/third_party/ckfinder/userfiles/files/xamopigugo.pdf
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1f9ca82b76---bakewurufapefi.pdf
    • http://cck-brno.cz/ckfinder/userfiles/files/97029000155.pdf
    • http://hybsch.it/upload/file/42709097971.pdf
    • http://anatolianlgs.com/userfiles/file/kupaf.pdf
    • https://prcomponents.com/ckfinder/userfiles/files/tejuwa.pdf
    • https://grandhotelbulgaria.com/userfiles/file/77778096316.pdf
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d05f004799---57327843954.pdf
    • http://adabaskimerkezi.com/upload/file/8503426070.pdf
    • http://dintainoodle.com/uploads/files/82381439249.pdf
    • https://aodaixuan.vn/app/webroot/upload/image/files/70137017486.pdf
    • https://defi128.phpascal.com/userfiles/files/sedukofopejavudofilo.pdf
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1610c590685028---81972777549.pdf
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/7017c6b62385b41ceb6c22a5c0e893ee/mulesowoxapadimi.pdf
    • https://abandassociates.com/ckfinder/userfiles/files/12188781039.pdf
    • http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4d164be0c8---86991785769.pdf
    • https://www.endthestigmacounselling.com/wp-content/plugins/super-forms/uploads/php/files/0i86s8finosctemb57m3agu9fc/5907746895.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=physical+and+chemical+properties+of+alkanes+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e9fb.bin
f441dbee4af4c6e7f0ccef1f675ff1178880ad2064862a52d3ff4aad53d7fe8c
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9FB 11092 bytes
font_01_sfnt_off000103a8.bin
f458160a206cb26cd9f1a46bda476d76467a762b75b4accca558c6c753a45d1c
pdf-font-stream PDF embedded font (sfnt) at offset 0x103A8 18708 bytes
font_02_sfnt_off00013397.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13397 16792 bytes