Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1c66a6001986658…

MALICIOUS

PDF

86.7 KB Created: 2021-09-18 06:43:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: f8300b77fe55604ed09cdeb05284d3b5 SHA-1: 3aa541d1d3dad607a0e9a9108b055123b27ca1c4 SHA-256: a1c66a60019866581f0ec8342dbcb789104d7d3abce6aafcb9fc7dcb78879ad0
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple potentially compromised or disposable hosting sites. The presence of numerous embedded URLs, many pointing to suspicious domains, supports the conclusion that this document is designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://mannadey.in/FCKeditor/file/bumapapamobuwinorobavi.pdf In PDF document text
    • http://codemessaging.net/ckfinder/userfiles/files/21634610407.pdfIn PDF document text
    • https://open-call.fr/uploaded/files/25562260707.pdfIn PDF document text
    • http://jfhcoaching.nl/userfiles/files/57326849369.pdfIn PDF document text
    • http://wadsoda.com/UserFiles/File/38371274105.pdfIn PDF document text
    • http://internet-trade.eu/UserFiles/file/50801626188.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/16139b41d09bc6---tetenogirawikijo.pdfIn PDF document text
    • https://cailux.lu/userfiles/files/8172351830.pdfIn PDF document text
    • https://hojoairport.com/images/file/kexulevumusasi.pdfIn PDF document text
    • https://wic-net.com/userfiles/file/89780818274.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/lkp4tu7ur1cjn3mvi9fg8nguc6/ziwokogebovin.pdfIn PDF document text
    • https://wonwon.taipei/photo/file/43191302026.pdfIn PDF document text
    • http://positiveforce.in/uploads/files/37919663922.pdfIn PDF document text
    • https://ibericadearmerias.com/file/47722249772.pdfIn PDF document text
    • http://paradisetourkorea.com/FileData/ckfinder/files/20210902_44BCC802ABFC97F5.pdfIn PDF document text
    • https://magnanerie-cazilhac.com/userfiles/file/79661492521.pdfIn PDF document text
    • http://agilesolutions.in/uploads/71897294973.pdfIn PDF document text
    • http://manpukuorder.com/uploads/files/tirukit.pdfIn PDF document text
    • http://short-story.ru/upload/file/xijegitavopikegexapabu.pdfIn PDF document text
    • http://canvangdientu.com/images/file/41217974358.pdfIn PDF document text
    • http://shceping.com/upFile/photos/2021-9/file/61126974263.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613726dd4f43e---zanazudurusotilexizof.pdfIn PDF document text
    • https://riminabda.sk/userfiles/file/10313494980.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=sync+outlook+calendar+to+android+phonePDF 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_off0000ecec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECEC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000104fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104FE 18276 bytes
SHA-256: 314018ffe2dc39afc8860a14bceaaab5dec6bc7a6207151eb22c9770175b3a47
font_02_sfnt_off000133fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133FE 10824 bytes
SHA-256: 58bfb06a1c1840379f1122b6e3da501ddf069ffa3810e455df2cc0e3ae7d776e