Malicious PDF — malware analysis report

Static analysis result for SHA-256 e55b89da14beb53a…

MALICIOUS

PDF

70.4 KB Created: 2021-09-24 16:54:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6a9abc83e0c5ce31e13f0971d09e3961 SHA-1: ea24ea90451282e91bf537ca881db2b53a79ba78 SHA-256: e55b89da14beb53a9db381fc86325b0211d3c186f62ee35857edca6d40da0c42
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple heuristically flagged links to suspicious domains, with one specifically identified as a link farm on disposable hosting. The ML classifier and ClamAV also strongly indicate maliciousness. While no scripts were extracted, the presence of numerous external URIs suggests the document's primary purpose is to redirect the user to a malicious site, likely for phishing or to download a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/7dla6op3b1kq4lbak8aum6jc54/79308291270.pdf In PDF document text
    • http://rorolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/pejezipadisadafusosevi.pdfIn PDF document text
    • http://terezszilvia.com/images/uploaded/file/zawevanesakavuzelajusigad.pdfIn PDF document text
    • https://mehreganimaging.ir/images/upload/files/23641748960.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/16143becd29429---95510871151.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/gimrga8poas1rmp87g73v3efg5/4344446189.pdfIn PDF document text
    • https://ceiling.holcom.vn/webroot/img/files/sapavulijasaxetukeg.pdfIn PDF document text
    • http://asesorgubernamental.com/images/file/1366683242.pdfIn PDF document text
    • https://ijpdua.com/contents/files/gejamananidap.pdfIn PDF document text
    • http://retrievers.su/ckfinder/userfiles/files/bemumuxamixipinuj.pdfIn PDF document text
    • http://smenergy.kr/uploaded/file/874929607614847c5f1572.pdfIn PDF document text
    • https://pharma-tools.pl/galeria/file/pulanarinowegasusor.pdfIn PDF document text
    • http://tatvideo.ru/ckfinder/userfiles/files/pasusozavit.pdfIn PDF document text
    • https://hanoihome.net/img_duhoc/files/39744910823.pdfIn PDF document text
    • http://mp-hd.de/data/aktualnosci_imgs/file/14691015002.pdfIn PDF document text
    • http://boschvietnam.com/files/usersfiles/files/nakugavepuxawi.pdfIn PDF document text
    • http://www.koeru.eu/failid/file/kusajidujadojuribige.pdfIn PDF document text
    • http://sinching.com/uploadpic/files/202109120053012489.pdfIn PDF document text
    • http://www.enjoyvaltellina.it/admin/ckfinder/userfiles/files/22855216844.pdfIn PDF document text
    • http://anneadamslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/niziteminakopotupemurub.pdfIn PDF document text
    • http://heizler.hu/files/file/zilumuxuvuti.pdfIn PDF document text
    • http://bolshunoff.ru/images/wysiwyg/file/lilixunoduseruko.pdfIn PDF document text
    • http://www.nomorcantikjoss.com/file/63496496421.pdfIn PDF document text
    • http://conblocmanado.com/pics/file/24696025590.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=father+of+kratosPDF 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_off0000b422.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB422 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cc34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC34 16032 bytes
SHA-256: 62939acfd0340a22cb32cf687249df69ac36936ecfdf502dab786515757eeb2b
font_02_sfnt_off0000f524.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF524 10140 bytes
SHA-256: 3f42d8e7ec90db130e7ac4c670396709379a97550337439c7a1824a031cfed01