Malicious PDF — malware analysis report

Static analysis result for SHA-256 a98f05d991fcb2fc…

MALICIOUS

PDF

75.3 KB Created: 2021-09-13 20:28:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 16a6aa6bccb8e02c55812d192436c062 SHA-1: 1759a3883bc61675afdaacc0f0f67f57551b2cb1 SHA-256: a98f05d991fcb2fc8668513c96e9258dc22dd44045f967e225e5f2ebe4ab2fef
156 Risk Score

Malware Insights

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

The PDF file contains a link farm, directing users to multiple external URLs, some of which are hosted on compromised CMS uploads or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or to serve a second-stage payload. The embedded URLs suggest an attempt to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://palenice.net/obrazky_clanky/file/81361364660.pdf In PDF document text
    • http://pomelieagency.com/userfiles/files/divutod.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/b6065e036bca9f7429471f59994353ac/rasevalorebevaliviw.pdfIn PDF document text
    • https://ms2gacor.com/contents/files/51104810818.pdfIn PDF document text
    • https://atlanticcompact.org/userfiles/files/65102430319.pdfIn PDF document text
    • http://dmhu.eu/uploads/uplib/file/levozijawago.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613a0d4ed8d16---19499450747.pdfIn PDF document text
    • http://gezond-trakteren.nl/kasteel-doornenburg-img/bestandenfile/14526564150.pdfIn PDF document text
    • http://clubesquilacoma.com/uploads/files/molixodalodinavofes.pdfIn PDF document text
    • http://mazraeir.com/images/upload/files/getorunusadazuvij.pdfIn PDF document text
    • http://shinaval.ru/userfiles/file/ketikibuvevoxob.pdfIn PDF document text
    • https://felicityokolo.com/file/44269511044.pdfIn PDF document text
    • http://xpeedon.net/userfiles/file/20210902053800.pdfIn PDF document text
    • https://u15.ch/ckfinder/userfiles/files/90660199816.pdfIn PDF document text
    • https://butchercurnow.com/img/shop/contents/65679322552.pdfIn PDF document text
    • http://stagticket.com/fck_upload/file/jatowajefininesuduti.pdfIn PDF document text
    • http://citysoupsbellevue.com/uploads/files/filovunipijededela.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137b690e8216---kitirudiroleniwuzumujev.pdfIn PDF document text
    • http://manchetenewsms.com.br/ckfinder/userfiles/files/ludomed.pdfIn PDF document text
    • http://termosystem.pl/userfiles/file/tatijujikop.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/246d5386c9dfb31f8480d5496f7f278d/fefilumotobupavam.pdfIn PDF document text
    • https://systematix.pl/userfiles/file/jejuk.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=kimetsu+no+yaiba+movie+full+subPDF 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_off0000be91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE91 10684 bytes
SHA-256: 1528f008c6fdac4a652c7abaff4c111dedecffd61921d06d634e6758b7622c6c
font_01_sfnt_off0000d727.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD727 18652 bytes
SHA-256: 75128d54f0980bb2964de01c87fe2f06df3c780ebb441417ab82a9730f1ab50a
font_02_sfnt_off00010789.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10789 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1