Malicious PDF — malware analysis report

Static analysis result for SHA-256 90936d45e4ead081…

MALICIOUS

PDF

76.4 KB Created: 2021-09-18 10:24:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: fdad7e6938968f4b395f977605fccb52 SHA-1: f1d1086234b4a72575cc603b013d45ac5cbf83a2 SHA-256: 90936d45e4ead08133509b64aee95fd34251e7793a7a8f4c07ee967a949a3573
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier, exhibiting characteristics of a link farm. It contains numerous embedded URLs pointing to compromised websites, including WordPress upload directories, suggesting an attempt to redirect users to malicious content or phishing pages. The presence of these links and the overall structure strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://laborke.ru/uplcv?utm_term=idle+ants+hack PDF link annotation
    • http://vesimport.ru/userfiles/file/59862845067.pdfIn PDF document text
    • http://anabakorea.jp/userfiles/file/81396336432.pdfIn PDF document text
    • https://iwistw.com/upload/files/26301353205.pdfIn PDF document text
    • https://ljlconst.com/admin/images/file/sasutidivala.pdfIn PDF document text
    • http://chelseacarpet.com/ckfinder/userfiles/uploads/82578200499.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613707d5d6d31---banibirirurek.pdfIn PDF document text
    • https://atlaskvartir.ua/data/uploads/files/6511494085.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613286b65ad86---1156906372.pdfIn PDF document text
    • http://maristaslardero.es/userfiles/file/93167224507.pdfIn PDF document text
    • https://asesoriagade.com/app/webroot/files/files/11213355750.pdfIn PDF document text
    • https://hw-power.com/uploads/ckfiles/files/613f643a669f8.pdfIn PDF document text
    • http://dr-onesrl.com/userfiles/files/53780276247.pdfIn PDF document text
    • http://ihanzao.com/userfiles/file/20210907144353_1632117619.pdfIn PDF document text
    • http://wsm.hk/images/files/79441165959.pdfIn PDF document text
    • http://eviljoy.com/UserFiles/File/17887729217.pdfIn PDF document text
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e1332cfdc2---batuvekoxemaxi.pdfIn PDF document text
    • http://xn--42-6kcdlkbomh7beggito5p.xn--p1ai/userfiles/file/8235970951.pdfIn PDF document text
    • https://grandplaza.bg/uploads/assets/file/15710732838.pdfIn PDF document text
    • https://sdudyogtechnologies.in/ckfinder/userfiles/files/14197540957.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_off0000c770.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC770 18176 bytes
SHA-256: 2dfb11b0c17e89c08d1ebd0e688ec2883675e08ff918e654a0c7881b0869a756
font_01_sfnt_off0000f5d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5D3 10196 bytes
SHA-256: ff98a63636e7a84c7c24349b5da9a00c6617b8e423279e5c6471231b9c1ee920
font_02_sfnt_off00010ca3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CA3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1