Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f85f1d2ac5a6924…

MALICIOUS

PDF

98.5 KB Created: 2021-09-17 17:07:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0fcec5521dd629b8002c1a5fb203539e SHA-1: 925daed5cb7f4641c7d848752d3b6bf46a956afe SHA-256: 9f85f1d2ac5a6924579110e79cd6eb5b80e4b9e32a95651ab21324963ac494d8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs that point to various domains, many of which appear to be compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using non-clustered link farms on disposable hosting, suggesting an attempt to obscure the true malicious destination. The presence of external URIs and link farms strongly suggests the document's purpose is to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://crysiq.ru/uplcv?utm_term=constantine+full+movie+eng+sub
    • http://leeharringtonhomes.com/userfiles/file/4394514647.pdf
    • http://arunimaflavours.com/userfiles/file/16112067767.pdf
    • https://efficientinfocomm.com/ckfinder/userfiles/files/jatosiwomovabites.pdf
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/16136a8d956a01---74132298989.pdf
    • https://clifestyle.net/uploades/userfiles/file/16260302626.pdf
    • https://wyslijpaczki.pl/app/webroot/files/userfiles/file/19016949363.pdf
    • https://trungtamgiasuhcmmq.com/uplaod/quangtri/files/zerimedex.pdf
    • http://scard.vn/app/webroot/uploads/files/36290223597.pdf
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/5dauap5cjticahu7pu7rfkldcf/wuwiwamifivemikedinufusiw.pdf
    • https://jensbrode.de/files/file/38199923483.pdf
    • http://sbnjl.com/userfiles/files/zimofobitujefusip.pdf
    • https://oriental-kitchens.com/userfiles/files/wexakegawomedujuv.pdf
    • http://kapelski.pl/userfiles/file/lovexatajotoved.pdf
    • https://indiachristian.org/uploads/files/mifogimezak.pdf
    • http://proart.by/media/file/25636272891.pdf
    • http://mtegl.wsystem.sk/userfiles/files/41443462755.pdf
    • http://lixupeng.com/uploads/files/76930629616.pdf
    • http://gernano.eu/gfx/userfiles/files/ziranufimeminafuzuji.pdf
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f26c0a6e0b---54860332664.pdf
    • http://jr-bang.com/uploadfiles/20210905225100.pdf
    • http://www.golfusa.be/userfiles/files/76761877359.pdf
    • http://adaviestransportltd.com/userfiles/file/80214870486.pdf
    • http://delannahotel.com/user_img/file/25146975676.pdf
    • http://clinicaveterinariagoitese.it/userfiles/files/14123782890.pdf
    • http://chnli.tw/CKEdit/upload/files/52258045890.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000118eb.bin
e761e4d9dda0a4898ba4b33da981364f6cab9714b61a32b922c4f40079398740
pdf-font-stream PDF embedded font (sfnt) at offset 0x118EB 19128 bytes
font_01_sfnt_off00014b2d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14B2D 16792 bytes
font_02_sfnt_off00016344.bin
2b3f61fa773b3378b15a24ca6d56a4d95330b5560014c384657b66be3ee0ea8b
pdf-font-stream PDF embedded font (sfnt) at offset 0x16344 10792 bytes