Malicious PDF — malware analysis report

Static analysis result for SHA-256 891e5dabac3968ad…

MALICIOUS

PDF

79.2 KB Created: 2021-09-16 18:57:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: f22915650f7e201ef644649357dab659 SHA-1: c83e67200d2f40a21732f39f8f388ce22f8f2a94 SHA-256: 891e5dabac3968adcca2696b6aefec8b382d40807a5a1138f540969382ddfeeb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. The heuristics indicate the document functions as a link farm, directing users to multiple potentially compromised or disposable hosting sites. The presence of numerous PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM firings supports this, suggesting an attempt to distribute malicious content or conduct phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://4bx.pl/public/file/tuwenewopixurifibewoxun.pdf In PDF document text
    • http://xn--b1agaa2anfqdp.xn--p1ai/ckfinder/userfiles/files/7085011060.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d028312323---votofupevifazusefib.pdfIn PDF document text
    • http://chrisdepanneservices.fr/Sites/cds/files/gepil.pdfIn PDF document text
    • https://dungcuruamui.com/wp-content/plugins/super-forms/uploads/php/files/ft1t87aeoin6e0t2aln2hsldjl/21457376822.pdfIn PDF document text
    • https://esportenerd.com/app/webroot/ckfinder/userfiles/files/35777563150.pdfIn PDF document text
    • https://shivajigrihnirman.com/singhania/downloads/file/tigadojoximanusugakaziva.pdfIn PDF document text
    • http://phukientubepxinh.info/gomsu/sanpham/anh/files/62692476652.pdfIn PDF document text
    • http://aldobini.it/userfiles/files/lokejeludobatonorer.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/4eddbb3d2aa9ba41bde4dcd12d283fd6/57119131236.pdfIn PDF document text
    • http://tehpromyar.ru/media/file/84090147642.pdfIn PDF document text
    • https://artinterior.bg/userfiles/file/33457024344.pdfIn PDF document text
    • http://vanguardhungary.hu/userfiles/file/95040862319.pdfIn PDF document text
    • http://archive-2014.humandoc.pl/attachments/file/48459345155.pdfIn PDF document text
    • http://architettoletiziamasciotta.eu/userfiles/files/98471319347.pdfIn PDF document text
    • https://picinterior.com/ckfinder/userfiles/files/53274673341.pdfIn PDF document text
    • https://indiantalentjunction.com/milan/media/korojosisonim.pdfIn PDF document text
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/16137c1d14be02---65197233094.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16142030616e8f---53224755129.pdfIn PDF document text
    • https://behbehaniprojects.com/uploads/files/berukaxiwexofem.pdfIn PDF document text
    • https://heuresromantiques.com/upload/files/zudejor.pdfIn PDF document text
    • https://rossbeede.com/userfiles/file/gofakorupijibumebasuzu.pdfIn PDF document text
    • http://hulstcustoms.ru/uploads/files/95151684453.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=docs+viewer+apkPDF 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_off0000d2b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2B3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eac5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAC5 17556 bytes
SHA-256: af1efdc21a6e6144ede0b574620aab1efc86b85d4e7522a20de5837c48935079
font_02_sfnt_off00011803.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11803 10364 bytes
SHA-256: 103b9cfe26e7eec53ef903fe0f37edb5eed3cf683a692253494ce6371002f287