Malicious PDF — malware analysis report

Static analysis result for SHA-256 5ca7598d57f20626…

MALICIOUS

PDF

87.0 KB Created: 2021-09-15 20:44:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 0745353e09f47c305b5798f3dfade175 SHA-1: e52e2cb829fa4477075013a243fbbc56d58edc3e SHA-256: 5ca7598d57f20626fe99924e4c3d7271c17700dd4d25522726a574f03ad62966
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs that point to a link farm, suggesting a phishing or SEO manipulation scheme. While no scripts were explicitly extracted, the presence of external URIs and the link farm structure strongly suggest an attempt to redirect users to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://www.siphonicflowmandiri.com/upload/files/vemazuxoniraduriboki.pdf In PDF document text
    • http://sendedianqi.com/upload_fck/file/2021-9-14/20210914165425498731.pdfIn PDF document text
    • https://viadagio.be/userfiles/file/42032227511.pdfIn PDF document text
    • http://studiogeologicotrilobite.com/userfiles/files/gupikimusod.pdfIn PDF document text
    • http://podwierzba.eu/ckfinder/userfiles/files/6848038110.pdfIn PDF document text
    • http://www.phuongdonggolf.vn/app/webroot/uploads/files/memawemurifuses.pdfIn PDF document text
    • https://ivanda-commerce.hr/userfiles/file/22778500676.pdfIn PDF document text
    • http://psycare-spb.com/userfiles/file/58159692836.pdfIn PDF document text
    • http://mopi.eu/ckfinder/userfiles/files/17227707221.pdfIn PDF document text
    • http://waycreon.net/bhaskar/yii/upload/files/wenizuzarapu.pdfIn PDF document text
    • http://thaymanhinhlaptop.com/userfiles/file/46377172564.pdfIn PDF document text
    • http://ericshartman.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/89194238024.pdfIn PDF document text
    • http://xboxheerlen.nl/userfiles/file/76827941025.pdfIn PDF document text
    • http://autowassenindex.nl/images/uploads/10038419626.pdfIn PDF document text
    • http://fc-junajted.com/upload/datoteke/70081638447.pdfIn PDF document text
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/qaooaiu4t947jv1mgvfto6vaie/simegil.pdfIn PDF document text
    • https://masukpt2.com/contents/files/pikanowujorifopa.pdfIn PDF document text
    • https://mikludava.lt/images/files/juvewekedodisokidavabi.pdfIn PDF document text
    • https://www.domaine-de-la-ferme.fr/ckfinder/userfiles/files/kuvizo.pdfIn PDF document text
    • https://xn--dokumaanahtarlk-llc.net/userfiles/file/5276177096.pdfIn PDF document text
    • http://mishelik.ru/userfiles/file/mafadagutogopito.pdfIn PDF document text
    • http://argol-editions.fr/userfiles/file/91090117495.pdfIn PDF document text
    • http://ijdssymposium.eu/upload/zuvudikositoduninomubos.pdfIn PDF document text
    • https://thefertilizerequipment.com/d/files/89478155951.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/161310b47dd564---gomazukowawamu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=background+eraser+apk+proPDF 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_off0000e721.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE721 10696 bytes
SHA-256: f6ca056464de7ecdb7839d958d07ee21771425c403bea00e5f0a269a626ebdff
font_01_sfnt_off0000ffa3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFA3 20776 bytes
SHA-256: 78808cae69219980f09bb38bdec1356a6d8a31bf2677bf53a0924828cab2dd27
font_02_sfnt_off000135f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135F2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1