Malicious PDF — malware analysis report

Static analysis result for SHA-256 73ae40208904db2a…

MALICIOUS

PDF

77.6 KB Created: 2021-09-12 19:36:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ae634a697550463461403608c47b3d5a SHA-1: eecdc20c420e9310ff14f5fe1193025e8bc95810 SHA-256: 73ae40208904db2a829c5b8c5217c376b9dca91a949ad65f3a8fbea4e8be0da7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous external URIs and link farms, with a significant portion pointing to compromised CMS upload storage. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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 https://ketchas.ru/uplcv?utm_term=adblock+ultimate+extension+for+chrome PDF link annotation
    • http://image.dlib.vn/libedu/news/bachviet/20210910/file/36767138626.pdfIn PDF document text
    • http://quartierdete.fr/uploads/fckeditor/file/dolexeribos.pdfIn PDF document text
    • http://ayurveda-shiatsu-nice.com/upload/files/sefumexixepatebupigi.pdfIn PDF document text
    • http://www.thaiboat.net/image/upload/File/muvenakozisofagu.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/5arvshd17613cn6c3u685sv676/18770369620.pdfIn PDF document text
    • https://micro-logic.ro/images/uploaded/file/gifonosisolusukopotibenir.pdfIn PDF document text
    • https://proektasis.gr/admin/spaw2/uploads/files/balufutojarukarafi.pdfIn PDF document text
    • https://www.tahitotfalu.hu/ckfinder/userfiles/files/gozugor.pdfIn PDF document text
    • http://playbabydoll.com/userfiles/file/30824373161.pdfIn PDF document text
    • http://esipro.be/userfiles/file/44724093879.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/16136e94b9a220---notowevomiravo.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16133c209c449a---wisuvokebakot.pdfIn PDF document text
    • https://rhuyscampingcar.fr/images/files/nunawazonesigejevogi.pdfIn PDF document text
    • http://luberoff.com/userfiles/file/53526728439.pdfIn PDF document text
    • http://rheumatology.institute/upload/content/file/25660265351.pdfIn PDF document text
    • http://sbstroy53.ru/img/files/29131925556.pdfIn PDF document text
    • https://millinerandassoc.com/files/file/30253757643.pdfIn PDF document text
    • https://tranthachcaodanang.com/uploads/image/files/weripusifipoj.pdfIn PDF document text
    • http://associatedreclaimed.reclaimedoils.com/userfiles/files/44495719853.pdfIn PDF document text
    • http://stainless-faucet.com/uploads/htmlupload/files/52290596478.pdfIn PDF document text
    • https://zlato-stribro-investice.com/upload/files/75248540536.pdfIn PDF document text
    • https://ags-car.60km.com/upload/files/23727419054.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_off0000c921.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC921 17828 bytes
SHA-256: 354c505bac9ed448eeef82167f172cd9af9aee0a530688b35051860e800be6db
font_01_sfnt_off0000f73e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF73E 11156 bytes
SHA-256: 9d8c881efd752ed1dee8a2585f60b93436f4032360d9b6030698d52859996ccd
font_02_sfnt_off0001111d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1111D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1