Malicious PDF — malware analysis report

Static analysis result for SHA-256 162651f0fa3936d3…

MALICIOUS

PDF

71.0 KB Created: 2021-09-11 16:14:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 7a406755e81c5e509d1c8c9464976752 SHA-1: a366edb34e3f63d99a7439aa23ec66bb89e6f242 SHA-256: 162651f0fa3936d3224c39d1122af568b798b9463eb0b0668f405e46ec4eb8d7
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external URIs, indicating malicious intent. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document is designed to redirect users to numerous disposable hosting sites. The ML classifier and ClamAV detection strongly support a malicious classification, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://pixomot.ru/uplcv?utm_term=free+children%27s+books+download+pdf PDF link annotation
    • http://eichler-kammerer.de/telufifonik.pdfIn PDF document text
    • https://hotelharmika.com/assets/userfiles/files/4519681332.pdfIn PDF document text
    • http://hoangminhsaigon.vn/@dmin/js/ckfinder/userfiles/files/danitasatose.pdfIn PDF document text
    • http://www.heksan.com.pl/file/62986478875.pdfIn PDF document text
    • http://domuran.pl/files/file/91724936038.pdfIn PDF document text
    • https://soechi.com/userfiles/file/juvobufazupilenasedosiwa.pdfIn PDF document text
    • http://flapboxes.custompackageboxes.com/userfiles/files/1490604596.pdfIn PDF document text
    • http://automotiveenergy.cz/userfiles/file/2015916599.pdfIn PDF document text
    • http://www.greddy.com/admin/common/ckfinder/userfiles/File/92048326135.pdfIn PDF document text
    • http://smirna.pl/files/file/10907312750.pdfIn PDF document text
    • https://masihpt1.com/contents/files/metoresupotopom.pdfIn PDF document text
    • https://orangcar.com/app/webroot/upload/files/podos.pdfIn PDF document text
    • https://kitchensofdiablo.com/upload/file/lefawofigivotuvuzeseb.pdfIn PDF document text
    • https://nikosdimos.gr/userfiles/file/dadoravowe.pdfIn PDF document text
    • https://nolimitscenter.be/peausitive/images/FCKeditor/file/68346236819.pdfIn PDF document text
    • http://sourceit.ke/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/guxutilozojefaxit.pdfIn PDF document text
    • https://tasteadmin.com/ckfinder/core/connector/php/custom/wysi_uploads/files/nivirugul.pdfIn PDF document text
    • http://szwygs.com/upload/81493196078.pdfIn PDF document text
    • https://vnjhanoi.com/upload/files/lijujemaluba.pdfIn PDF document text
    • https://jotelek.hu/files/file/giwukinelidijitidejidi.pdfIn PDF document text
    • https://claudiodituri.it/uploads/99557763284.pdfIn PDF document text
    • http://wijnhuis-vaessen.nl/site/data/ws/files/moguwefogasigawoxekog.pdfIn PDF document text
    • http://hairfibers24.com/upload/file/soxatogolunat.pdfIn PDF document text
    • https://profession-your-dr.com/uploads/files/202109041956404685.pdfIn PDF document text
    • https://haidangpc.com/contents/files/bovokipubezojojutikej.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_off0000b615.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB615 15444 bytes
SHA-256: dbd76193c93b889598024468019c7849fed690a00d461250d9b297f63136e873
font_01_sfnt_off0000dd50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD50 10948 bytes
SHA-256: ce97945c628546aa76d818f3a2b98fabc5b8d928b7168423434680d9176f9aba
font_02_sfnt_off0000f66a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF66A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1