Malicious PDF — malware analysis report

Static analysis result for SHA-256 b77530611e9a293e…

MALICIOUS

PDF

81.4 KB Created: 2021-06-18 08:13:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: a41eaa15751b34b42579e6bc695c16b5 SHA-1: 05d6cabffb26e9c6834a9e6aa0346bcbe225cefe SHA-256: b77530611e9a293ebd9eaf6ae2a4fd73656c5aa347579cd29834a3d131d5048c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of embedded URLs, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The document body, though heavily obfuscated, contains references to movie downloads, a common lure for phishing and malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://crewmak.ru/uplcv?utm_term=humpty+sharma+ki+full+movie PDF link annotation
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609babf41b629---losekubatukulukuwatedu.pdfIn PDF document text
    • http://nnrhc.com/clients/9/98/980d61ede38c9a35fe3396fb65651545/File/61718357885.pdfIn PDF document text
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16083b88b34aac---42805448823.pdfIn PDF document text
    • http://wsm.hk/images/uploadfiles/file/jenevegisapazabi.pdfIn PDF document text
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609c1fe669505---natinifukafafo.pdfIn PDF document text
    • https://clubforeducation.com/FCKeditor/userfiles/file/50052274120.pdfIn PDF document text
    • https://northstarexecutivesearch.com/wp-content/plugins/super-forms/uploads/php/files/0e04578060e8b0a3653f58e93949b266/nugova.pdfIn PDF document text
    • http://al-bandak.com/userfiles/file/22345039396.pdfIn PDF document text
    • http://orhs89reunion.com/clients/77823/File/murezej.pdfIn PDF document text
    • http://dianacb.cz/userfiles/file/75938000539.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/4e5ea0af1489175b900612c6b32602d6/wumikugudenaror.pdfIn PDF document text
    • http://artside.org/data/temp/file/64321587793.pdfIn PDF document text
    • http://konyaozgunmobilya.com/userfiles/file/59776820749.pdfIn PDF document text
    • http://www.allatpatikapecs.hu/images/file/67066480340.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/160bfe41d8d267---jijefedowadofafosiz.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn 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_off0000e90a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE90A 5328 bytes
SHA-256: 1f8a1a86910728d38b035638a6781744f2f2c9e9532396f0fc352d1daa844c52
font_01_sfnt_off0000fb07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB07 11936 bytes
SHA-256: 18ce3d5cec22d82952df764e40d71eaf8607fa922ec3a7592d3b4a16f95be7d4
font_02_sfnt_off000123ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123AC 16164 bytes
SHA-256: e296a61d2d303e35be9e1a35631556663d2780498efa7e8f3867bf557f172fe6