Malicious PDF — malware analysis report

Static analysis result for SHA-256 662df5d2b3e5733c…

MALICIOUS

PDF

87.2 KB Created: 2021-09-01 02:30:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: ed70798f9c5d199660a6e31acc7507f3 SHA-1: d7d5ca366d0cc4dcacccf311ceba5fb812f7b46a SHA-256: 662df5d2b3e5733c88249ca78a7228675e3e9436e3fea9fb5a70bf33cb20266c
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file functions as a link farm, containing numerous URLs pointing to various websites, many of which appear to be compromised or hosted on disposable infrastructure. The ML classifier strongly indicated maliciousness, and the presence of multiple external URIs suggests an attempt to redirect users to potentially harmful content or for SEO manipulation. No scripts were extracted, limiting the analysis of direct execution capabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 5

  • 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://nomylo.ru/uplcv?utm_term=constituent+structure+in+syntax PDF link annotation
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160c6a61638667---tawinupoviwaki.pdfIn PDF document text
    • http://yasaitogo.com/uploads/files/78547627302.pdfIn PDF document text
    • http://matchedtubes.de/userfiles/file/91833458666.pdfIn PDF document text
    • http://mexvp.com/ckfinder/userfiles/files/lavupurevapoku.pdfIn PDF document text
    • https://medpressa.ru/files/file/merenasidotapixisidewuzo.pdfIn PDF document text
    • http://brcassociati.com/userfiles/files/9861797958.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/091a982183c25eda9cd6759512851f04/gimuleb.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611a1e8d0f6c6---tiwovajevudolavutenuled.pdfIn PDF document text
    • http://vizcsap.hu/files/file/43445342173.pdfIn PDF document text
    • http://hotelclinton.it/userfiles/files/48946543763.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/vosidawibaxekiramixoxez.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085b04f3ab1f---1786290808.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160942f1c13e87---nabifuzimolixok.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a98e204db9---zozujezotev.pdfIn PDF document text
    • http://mai-colle.jp/userfiles/file/28878353524.pdfIn PDF document text
    • https://hotellemaritime.com/hotel/upload/files/12401592232.pdfIn PDF document text
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/l7hrnnqr2jol7jm5jmiot4k7kh/winesagulanamekatu.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/c1e487da2ddf7d7fd045278e5bdd63e0/zunokaden.pdfIn PDF document text
    • https://bechtoldpaving.com/wp-content/plugins/super-forms/uploads/php/files/958e28831939d11218e58ccdf9927e76/37132918036.pdfIn PDF document text
    • https://sklep-pinokio.pl/web/uploads/files/moliwoxitemerigaka.pdfIn PDF document text
    • http://www.apsetedavisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fb82ed2e08---5955969712.pdfIn PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b425d753af5---vizoresewonu.pdfIn PDF document text
    • https://turasmobilya.com/img/editor/image/file/lepazerilavakipu.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609af5c7a45f2---18336316937.pdfIn PDF document text
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/7c1b3684ff606311d775338c58ba2cad/xabad.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_off0000f0d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0D6 10524 bytes
SHA-256: a9d11f0566cd3efcd70937013dca80a9ab4dd5f2ec2fa9a470a6a8e18029362b
font_01_sfnt_off0001090d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1090D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001211f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1211F 17804 bytes
SHA-256: ab62a5fd78b4cde51dad9a23ade4da614671b4d788eb0afb2d6f597876243d86