Malicious PDF — malware analysis report

Static analysis result for SHA-256 5ef6171bb7542ab9…

MALICIOUS

PDF

75.2 KB Created: 2021-09-05 10:23:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 97a58af56b4a742c46c81324a672c105 SHA-1: 052c85c7dd2301bd382daf62093e8878f0a920fe SHA-256: 5ef6171bb7542ab9a35b5694148444e0c387db413622e7e9991fba8b0cae6166
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated high maliciousness. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution lure. The document body was unreadable binary data, but the embedded URLs and heuristic findings strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/9490a31d7d4229f7b59b9883aed24ed7/bujisogepejudu.pdf In PDF document text
    • http://chingyi.tw/userfiles/files/7573852767.pdfIn PDF document text
    • http://attlas.center/userfiles/file/79373700401.pdfIn PDF document text
    • http://homeshopeez.com/uploaded_files/userfiles/files/6651834361.pdfIn PDF document text
    • http://jingluo.net/uploadfiles/files/59179071547.pdfIn PDF document text
    • http://discus-rus.ru/upl/file/23788949370.pdfIn PDF document text
    • http://shbaicun.com/userfiles/file/2021072208525573499.pdfIn PDF document text
    • http://xn----dtbfdwc0aaaev8k.xn--p1ai/ckfinder/userfiles/files/66996699588.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5d6f6336a2---moripulemitaru.pdfIn PDF document text
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/fu5nfjfmmtvcvs9mstmhkho238/danirerakesepifuwosonobez.pdfIn PDF document text
    • https://dhesient.com/media/59428473131.pdfIn PDF document text
    • https://www.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/o5hlkomm92r72m4f1g9tj2r9g1/selawulovuru.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0a5944b258---felejenusalup.pdfIn PDF document text
    • https://woodfur.in/userfiles/file/27516345783.pdfIn PDF document text
    • http://phuketdriveschool.com/userfiles/file/wuvilavedumakes.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608ef2fd052ad---jeditowus.pdfIn PDF document text
    • http://secohthailand.com/file_media/file_image/file/4716500898.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1609d31ad07285---46215989559.pdfIn PDF document text
    • https://dcimx.com/files/35549346074.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/4cmfn5db9m2sa9qea8encodu10/3911807084.pdfIn PDF document text
    • https://panegovernance.com/ourprojects/chowki/UserFiles/file/luluga.pdfIn PDF document text
    • http://cyuansheng.com/userfiles/file/71046274856.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087b5e62b66d---64134714328.pdfIn PDF document text
    • http://gasthaus-steinkirchen.de/img/editor/file/sevunu.pdfIn PDF document text
    • http://bsbcarpet.com/userfiles/file/mobesonapuguwikajozewolop.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/1608cabe77a172---pixofak.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=tus+fizyoloji+sorular%C4%B1+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_off0000c0b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0B2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d8c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8C9 10568 bytes
SHA-256: 2396fd22fec43a028af4432c91b2a321fb8d853f08b47996231f4911822d0c8d
font_02_sfnt_off0000f0e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0E8 18468 bytes
SHA-256: edbe10cc5d5fe139780375732b014119566ea168503382fd420fb81814cf1b4b