Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a505e613129f70f…

MALICIOUS

PDF

79.0 KB Created: 2021-09-02 18:18:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: 0b98216b39da3a14aa0d17c3366f7ad2 SHA-1: 7f85fb5093594a5776c07ff990468e1ef0f41bc3 SHA-256: 3a505e613129f70f8368997c1024520f962ba698e4011846369e8a6ff7ae8cc9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier with high confidence. It contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting it's designed to lead users to malicious content. The presence of embedded URLs and the overall structure indicate a link farm used for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://krisoc.ru/uplcv?utm_term=thermal+physics+pdf PDF link annotation
    • http://ucinnovation.ru/admin/ckfinder/userfiles/files/98217728378.pdfIn PDF document text
    • http://aristosaigonhotel.vn/uploads/files/xivunurosamiferotajav.pdfIn PDF document text
    • http://one9five.com/userfiles/files/91138383428.pdfIn PDF document text
    • http://adaviestransportltd.com/userfiles/file/kumofewawumutonebulogoso.pdfIn PDF document text
    • https://barcelonacentromedico.es/files/galeria/files/87504680654.pdfIn PDF document text
    • https://amatnieks.com/pictures/image/99506289360.pdfIn PDF document text
    • https://elitstroycraft.ru/source/file/xagexodefejojuxupuzifala.pdfIn PDF document text
    • http://zamel2.pl/userfiles/file/palatawiwapa.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1607d3b87343ef---81427100288.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/2050764259.pdfIn PDF document text
    • http://cs-golfclub.com/ckupload/files/11272799809.pdfIn PDF document text
    • http://iccjsc.com/images/uploads/files/wizupofulejavoxidonanat.pdfIn PDF document text
    • https://artgreen.vn/attachment/files/zijotizafas.pdfIn PDF document text
    • https://signaturetowerpune.com/wp-content/plugins/super-forms/uploads/php/files/nusvgnmf9e2l1p1oj6m4fg72c5/47537714625.pdfIn PDF document text
    • https://shared401k.com/wp-content/plugins/super-forms/uploads/php/files/ddeb2d7a86b7d08af67af21cbed1dd04/netefipigubem.pdfIn PDF document text
    • http://papierplus.pl/userfiles/file/zibolegafajerutexoxedesu.pdfIn PDF document text
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/4bf17391673b2629db8ab8ac45221dd1/72607336274.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/160f72bfcad759---32934876835.pdfIn PDF document text
    • http://sjhrz.com/images/upload/File/14173748908.pdfIn PDF document text
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160db6e4c3265e---61376171535.pdfIn PDF document text
    • https://monographie.com/ckfinder/userfiles/files/renirexofapexaxidu.pdfIn PDF document text
    • https://dadrarad.ro/userfiles/file/fitatipovodum.pdfIn PDF document text
    • https://cottonweb.net/userfiles/file/mifup.pdfIn PDF document text
    • 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_off0000d452.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD452 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC69 10640 bytes
SHA-256: fbad893923a0571026a7bd142e4145897d0809db86b70797db059c3d9af19e74
font_02_sfnt_off000104c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104C0 16232 bytes
SHA-256: efb1d2eab902dca3e3731df664d9160d290c0fc7eb0c9312edb401470ef5ee2b