Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c830c8adcf36cb2…

MALICIOUS

PDF

84.2 KB Created: 2021-07-15 22:15:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4127736c1eaf3bae29eddb5223874590 SHA-1: 483a61786746d7544ddb2d0fa230c3c287bacaf5 SHA-256: 9c830c8adcf36cb2d7608231c93dc23f553414271b1e0124218ebac50336c156
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many of which are hosted on compromised CMS uploads or disposable domains, suggesting a link farm designed to redirect users to potentially harmful content. The presence of embedded URLs and the nature of the heuristics point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://amirep.com/wp-content/plugins/super-forms/uploads/php/files/641abba76258e89f6e087e335f19a5c0/wezomobeteg.pdf In PDF document text
    • http://esistore.be/userfiles/file/87322464970.pdfIn PDF document text
    • https://ecowaytechnologies.com/ckfinder/userfiles/files/14307364149.pdfIn PDF document text
    • https://www.ergunaygoren.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7c48a051e---dexekurexaxoge.pdfIn PDF document text
    • https://chpcentre.com/files/file/20472529233.pdfIn PDF document text
    • https://cristalensi.com/public/File/nujiwu.pdfIn PDF document text
    • http://www.franklinwebdesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160901072e5a6f---kafijaxori.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a71a18d19c---vinana.pdfIn PDF document text
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/h5f6ka0gc2v7fgo6h7lep2mn8e/kurofon.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160afded93bb33---96287468945.pdfIn PDF document text
    • http://atol-res.pl/uploads/file/23275069543.pdfIn PDF document text
    • https://mziagroup.com/wp-content/plugins/super-forms/uploads/php/files/4ohcj0fhievki97ru1fro7me7s/zepupikozakifanewe.pdfIn PDF document text
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/0et8irtm2qjcl88ma8tqvvhgmk/90354686185.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607e8ae32bf75---dikarowuwedepeboxata.pdfIn PDF document text
    • https://alkalacarservice.com/public_html/userfiles/file/16230556997.pdfIn PDF document text
    • http://es-manzokudou.com/yamituki-n/uploads/files/mipuxufutula.pdfIn PDF document text
    • https://grafitpoint.ru/wp-content/plugins/super-forms/uploads/php/files/659ea4c4ff97c44ff70afc115a80fd6e/rudemamipadonalibalof.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/irj8k4b4cfvbmrdt5qn4klrale/ganiziduluw.pdfIn PDF document text
    • http://budka39.ru/files/93082367679.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160be45699eae6---nofugoletabudewoxibab.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/160cfca269a94c---tekumuwarudebuzurofibupi.pdfIn PDF document text
    • https://hotel-la-licorne.fr/userfiles/file/21553955040.pdfIn PDF document text
    • http://aeronautike.com/userfiles/file/92322955419.pdfIn PDF document text
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/ecb6bc219dfebcb25ab7bf520ebbfdf9/sotarikazuvisigedibutok.pdfIn PDF document text
    • http://rotarylaspalmas.orgdocumentos/file/mazabaru.pdfIn PDF document text
    • https://pousadamarazul.tur.br/wp-content/plugins/formcraft/file-upload/server/content/files/16085a5afced05---25188645378.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=subtracting+a+negative+number+is+the+same+asPDF 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_off0000e4a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fcbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCBD 10892 bytes
SHA-256: e78591a62f248df18996caa4682258bfa275e5ce7f463e550b7d241b73733a25
font_02_sfnt_off000115c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115C4 17224 bytes
SHA-256: 43dd90fb91978c3372a3108a391702afa46493bbd74e5816a96426e413c894d7