Malicious PDF — malware analysis report

Static analysis result for SHA-256 56cda575ced57afb…

MALICIOUS

PDF

83.5 KB Created: 2021-07-02 06:51:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 07d4d0749b115bcade79b3484443dd70 SHA-1: b3be28ce96d940d9daccf8bb2227b7857efc6a70 SHA-256: 56cda575ced57afb75411c195c1c789ad1a43544604cf5190612299408751b5a
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites, identified by heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. The ML classifier and ClamAV also flagged this file as malicious, indicating a high likelihood of it being used for phishing or distributing further malware. The embedded URLs are the primary indicators of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/16072b0544e18b---89709354613.pdf In PDF document text
    • http://podiummoda.ru/userfiles/file/13805441267.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/160c5b92a7d92d---kukijuwomirofezis.pdfIn PDF document text
    • https://xo-sound.ru/userfiles/file/zusifuwaruxadevumotud.pdfIn PDF document text
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606f6bf0918b8---dadimukojojitikonulep.pdfIn PDF document text
    • https://laps.pl/userfiles/file/gamexixefadogevavatotebeg.pdfIn PDF document text
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/301e955ce8a04a60e06bb1b9535cedf6/lesure.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609481afcfa6b---15624748062.pdfIn PDF document text
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b34e79508c2---65327517814.pdfIn PDF document text
    • https://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/sk0a5jptv5u2d44oknfksf0i9j/38202802491.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608ff186a46f9---39139009487.pdfIn PDF document text
    • http://valleypainclinic.org/userfiles/file/laxaxilej.pdfIn PDF document text
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/e27qeur9sdtnj55o0ap4rng4ln/47943292775.pdfIn PDF document text
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/22b1d39f7481c6228167faf118dafc3d/86066550669.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080af1316ac4---18131975666.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/48c0b8fc14c7adb5061bf9fcf4b7dd0f/ruzirenajipadejegunoju.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=resthaven+park+cemeteryPDF 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_off0000e105.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE105 18176 bytes
SHA-256: 8ede389052f98d065da9d077127c4ffba3c12195854d0a8da25beba67c567abe
font_01_sfnt_off00011121.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11121 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012938.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12938 10700 bytes
SHA-256: c652d42f3126fd76add35fef8d9a8ae168514bba4ced04e78f9cf97ac22b6728