Malicious PDF — malware analysis report

Static analysis result for SHA-256 158e8c223d0a9c78…

MALICIOUS

PDF

75.7 KB Created: 2021-09-01 22:28:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: b64ff1665a794cade7a7e56a5cc30bed SHA-1: 5da71a0fece07cf91119c6a9054ec2d973a659a5 SHA-256: 158e8c223d0a9c78fdd866ffdf5988e4d1017d1b1364b130166f0b51db5831bc
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external URIs, many of which point to compromised CMS upload storage or disposable hosting, forming a link farm. Embedded JavaScript streams are also present, suggesting potential for further malicious actions like downloading additional payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://krisoc.ru/uplcv?utm_term=norman+gulley+systematic+theology+pdf PDF link annotation
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d0852c1f4e---xuwetemamomeku.pdfIn PDF document text
    • http://goteneplast.se/files/images/file/fexulapemiwajojekukelep.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608531c521f32---38582543476.pdfIn PDF document text
    • http://www.yeosung21.or.kr/ckfinder/userfiles/files/1629443205.pdfIn PDF document text
    • http://fashioneducation.ru/userfiles/file/58373737148.pdfIn PDF document text
    • http://monkey-do.net/userfiles/file/novawulesipiwupogiw.pdfIn PDF document text
    • https://tch.lu/files/files/wujakopuk.pdfIn PDF document text
    • https://firesystem.ro/imagini_ws/21887932506.pdfIn PDF document text
    • http://jjmcp.jp/userfiles/Image/file/zolelimomuzifumegovapi.pdfIn PDF document text
    • http://namkhoabacninh.com/images/files/34599321145.pdfIn PDF document text
    • https://marblo.ph/app/webroot/img/files/59823542834.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a022a3bb9ef---dereloxolejuronu.pdfIn PDF document text
    • http://circuitvietnamcambodge.com/hinhanh/file/16616659938.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abe604875f6---vakilunogusesawopo.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/f14205c8f7e406292ea7ffbf568e8ca7/fozipebovumusomo.pdfIn PDF document text
    • http://ramenzoni.eu/userfiles/files/60160093060.pdfIn PDF document text
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3ef752f70a---mupikafubufefupitun.pdfIn PDF document text
    • https://smsenerji.com/resimler/files/lubusepigejubewexujesode.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c988d501a78---bifufawug.pdfIn PDF document text
    • https://siroyensao.com/upload/files/sobojozefavemoreluzafexaf.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608ee038beebb---sanelalimirebo.pdfIn PDF document text
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/c562d5e9956ccadab3133531d5bd8879/39991413785.pdfIn PDF document text
    • http://budohurtsa.pl/userfiles/file/vinanaziledotorojimume.pdfIn PDF document text
    • http://www.llmhospital.com/www/js/ckfinder/userfiles/files/retobidijugisunujubon.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_off0000c204.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC204 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000da1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA1B 11256 bytes
SHA-256: 626d97e2166f6f407929c84b5394a205896431744133457e54a03aa415f24f93
font_02_sfnt_off0000f425.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF425 16644 bytes
SHA-256: a2168b97804064691c60dccaefd11964998d49ec840a93391b14a9c9451845a6

Open this report in the interactive analyzer, or submit your own file for analysis.