Malicious PDF — malware analysis report

Static analysis result for SHA-256 57d1ccc955a0cb57…

MALICIOUS

PDF

85.3 KB Created: 2021-06-29 03:47:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: e8bab8f8f139e4a39fb98a7ec9a83f62 SHA-1: c537ba53c0aa22789e80382955ab874d088162c5 SHA-256: 57d1ccc955a0cb578386632f920fe0823b1d19049073a690c385e56268c39577
156 Risk Score

Malware Insights

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

The PDF document contains numerous embedded URLs, many of which point to compromised websites or are part of link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware distribution sites. The presence of multiple links on potentially compromised CMS upload storage suggests an attempt to obscure the true destination and evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://advik.net/userfiles/file/42037191049.pdf In PDF document text
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/8cf01839e06ac3813e9e7515e3ded9e7/97141059742.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/160c10473b2168---vadiva.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/507dd4e31293036993774b1ee8c8d156/40795455779.pdfIn PDF document text
    • http://goref.ru/files/file/14750653337.pdfIn PDF document text
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/df60esnp0mpnuaslppcm81nfo8/sowibi.pdfIn PDF document text
    • http://ha-sine.com/d/files/71573686671.pdfIn PDF document text
    • https://burlingame.com/wysiwygfiles/file/40947490912.pdfIn PDF document text
    • http://pogservice.ru/userfiles/file/vikalujatitawog.pdfIn PDF document text
    • https://cafesca.mx/ckfinder/userfiles/files/xoper.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c98f81eb8b3---76839192700.pdfIn PDF document text
    • http://mfcwestenkwartier.nl/beta/userfiles/file/gukolute.pdfIn PDF document text
    • https://cubic.is/userfiles/file/gagumepi.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/160881a3c38b4a---lulubikisituxaj.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/9dcfe6b4c65e7dc31a5402b6e139fb02/gupelugaduxaxebetalawagen.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cb2f0186a2---debibiserebon.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608464354e2ff---zinugonaxatufipogemosu.pdfIn PDF document text
    • https://medtek.vn/storage/file/72717852816.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7ac8d20605---66348401172.pdfIn PDF document text
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a50d9b095bd---37199172132.pdfIn PDF document text
    • https://cooperspick.com/files/loralamukovokogewaviwale.pdfIn PDF document text
    • https://ilc.ua/wp-content/plugins/super-forms/uploads/php/files/8t0r9r0m1e6n6j45uf0ru97jg5/zesazimivebapikuledobibu.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d7fc7993f0---sososokirusadoso.pdfIn PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/52adf0c7136e5b63d183e9f7e42c6629/gajawavaxurefije.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/3ffb830dfdca702553118bbdf4dfd414/labugunukazisakapidoxaj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=need+you+here+with+mePDF 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_off0000e70e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE70E 19716 bytes
SHA-256: 2cadf0064e62d2db0a39db3fda8f40a4fb1fed3f0e99fbd586098425da0266de
font_01_sfnt_off000118f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118F3 10312 bytes
SHA-256: 790d74ecde2e521b8aed8087d5ea9ad0817075c79a06028aaf085c6ce126b3d1
font_02_sfnt_off0001303f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1303F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1