Malicious PDF — malware analysis report

Static analysis result for SHA-256 1da78111e7eb114d…

MALICIOUS

PDF

89.0 KB Created: 2021-07-09 15:05:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 4ecd9aebf0c1c9c20841d9a3a7cbb3d4 SHA-1: 167ed59ec3db7cc73eb2205ca885e450af240b98 SHA-256: 1da78111e7eb114de944e1e24d973b4b667cdb4d4519f85464f1873f38a5ec6e
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to compromised WordPress sites, designed to trick users into downloading a fake Adobe PDF Reader installer. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the link farm suggest an attempt to deliver a second-stage payload, likely via JavaScript execution within the PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 7

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/6dc7c6e328fbeea7c59d6e6ad2a02e10/17061707423.pdf In PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160750c0f14a6f---kurexubejiwe.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/p4elnve2qsm7f7oaevgvdur0rj/75994727338.pdfIn PDF document text
    • https://kimtuong.vn/isc/public/files/fckupload/file/5614276418.pdfIn PDF document text
    • https://lederstuehle-shop.de/ckfinder/userfiles/files/79162603830.pdfIn PDF document text
    • https://omomediacion.com/wp-content/plugins/super-forms/uploads/php/files/ec0a35de890d55597d2a2be1f2db03ab/zugevavuwuvat.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa0a7ce3a95---gawiwonuvaxixoteno.pdfIn PDF document text
    • http://komputerzagrosze.pl/userfiles/file/52870294501.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ac7dae8b54---96698775703.pdfIn PDF document text
    • https://aedwea.com/upload/foto/dolexaselipagozot.pdfIn PDF document text
    • http://crystalnymph.by/wp-content/plugins/super-forms/uploads/php/files/64c3eed398d10559ef736f93d51126b6/57333403781.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071fa3578d61---kuvuxifigij.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/0qk5md5udboe088tmsvkeikmi2/lutivexibezo.pdfIn PDF document text
    • http://pelesiuvalymas.lt/i/File/mimodikunosamunufodivize.pdfIn PDF document text
    • http://1960vonsteuben.com/clients/d/df/dfb5e1b83ea85bfdc5ef1da934264264/File/5331137507.pdfIn PDF document text
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/83704cd49e33fc728304247e3f84cf78/wepujavujivesanarogozux.pdfIn PDF document text
    • https://thetitangroup.ca/wp-content/plugins/super-forms/uploads/php/files/d10e1fe938470071d2798c020ac56d0e/kalupixixajazude.pdfIn PDF document text
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/b905b264162ddb5789b88e2c2c97dbdf/kixade.pdfIn PDF document text
    • http://mynigaoe.com/upload/file/20210706082506.pdfIn PDF document text
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f7638a1e2e8877d48b1e08529a02b0d2/43735555283.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092cb6825250---57359290774.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3207ca8035---97789774830.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c76ecb810e0---zitifesotukisexodizavuj.pdfIn PDF document text
    • https://camgloberealtor.com/userfiles/file/36728860988.pdfIn PDF document text
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/7um0aq64kgotbec8pqv8vav96k/6368871262.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=adobe+pdf+reader+for+windows+7+professional+free+downloadPDF 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_off0000fa07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA07 10648 bytes
SHA-256: 904aeb45004f9541558b7005bea38d8ec703ce31c9427b701cb65b148086b12d
font_01_sfnt_off00011265.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11265 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012a77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A77 16856 bytes
SHA-256: c7b00643fe5e53b4ad9cfb6429c9e2793ad8c809faa77708027b1b259612a596