Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a91895b4ceaf40a…

MALICIOUS

PDF

84.8 KB Created: 2021-06-30 07:20:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 3abf65161ecdcc5bebd1a57088b2cd8d SHA-1: b493a3bd380059540d7373f6b8341d951bb00913 SHA-256: 8a91895b4ceaf40af2e2785beb7e9b02a5d21af29a49c41010fca90f824d2436
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous URLs, many of which point to compromised CMS uploads or are part of a link farm on disposable hosting, suggesting an attempt to obscure the final destination. The presence of external URIs and the nature of the heuristics indicate a likely phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/8ce4bcb0c26f1b5070a6b7ebe987dc44/konegipataperu.pdf In PDF document text
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160bfbf46eb4cb---jejogoxiwituvuvak.pdfIn PDF document text
    • https://vinisfarm.com/wp-content/plugins/super-forms/uploads/php/files/d3961af47dc08782d6a0688c48a21fe6/92340337469.pdfIn PDF document text
    • https://karinbentum.nl/uploads/file/matuxoterixapanumuzozezow.pdfIn PDF document text
    • https://hitpoint.tw/userfiles/file/52993212466.pdfIn PDF document text
    • http://laxycoffee.com/upload/files/lotavod.pdfIn PDF document text
    • http://www.bandungmesin.com/file/kupunasebovaralijejuv.pdfIn PDF document text
    • https://www.hotwaterfactory.com.au/wp-content/plugins/super-forms/uploads/php/files/870fc9ec1b71e55e35b17780e56f08f1/wexigixavupavinuwap.pdfIn PDF document text
    • https://radmangroup-ye.com/rgfiles/file/derunuxopuzutafolonod.pdfIn PDF document text
    • https://seataclightingalaska.com/wp-content/plugins/super-forms/uploads/php/files/648d5cd62ac47e28ae2a7fbbf8a81a6c/22562554550.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/7sr0aervd4mh0g3e9dofi6atd2/68694638214.pdfIn PDF document text
    • https://comobrew.com/newsite/images/user_uploads/file/20556712103.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/160983eeadbe5e---xuxesavapekuriwofeta.pdfIn PDF document text
    • http://chineseclothingonline.net/File/42926115085.pdfIn PDF document text
    • http://gz-theoutfit.com/UploadFiles/FCKeditor/20210630060411.pdfIn PDF document text
    • https://techielingo.com/fck_uploads/files/wepuwofitirufuxel.pdfIn PDF document text
    • http://evola.it/userfiles/files/9504970676.pdfIn PDF document text
    • http://alliusie.com/userfiles/file/peluxokamekebavatetepe.pdfIn PDF document text
    • http://diplomat2014.ru/ckfinder/userfiles/files/67177085340.pdfIn PDF document text
    • https://vayamcs.com/content_files/files/32639232940.pdfIn PDF document text
    • https://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/rh65jp7h2jn237cj3u9pnfp8ai/raweretuvoruziwegaxefufa.pdfIn PDF document text
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f7109c2a051e4784e11344bcc1e1cb89/30114039686.pdfIn PDF document text
    • http://africareview.in/userfiles/file/39835489183.pdfIn PDF document text
    • http://cfh2.com/clients/d/d2/d2a7b52150a7a947468b52e9b7560e3c/File/lirewimanedixipisifini.pdfIn PDF document text
    • http://sicilyontable.it/userfiles/files/torazekokisorobamalenex.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=a+beginners+guide+to+the+stock+market+pdfPDF 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_off0000e7d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7D4 16876 bytes
SHA-256: 72350ced778a40e5f47f0294d31dc1f612694054182190977178576ac9ae958c
font_01_sfnt_off00011367.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11367 11332 bytes
SHA-256: e21ebfe6131ca30a5911b2a58efc3838656b7aaddf533d4ecbfc6bd3e4232876
font_02_sfnt_off00012d83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D83 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1