Malicious PDF — malware analysis report

Static analysis result for SHA-256 900a4874c3fc4520…

MALICIOUS

PDF

98.5 KB Created: 2021-07-13 22:03:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0ea995a414ca9309e14a5d48bd2c4ab4 SHA-1: 010cbb9fa7ba0a63bc56f879857e1cbdc49b7b3c SHA-256: 900a4874c3fc45203c27b4149279267a8686b9ccf6d6a7dee4b842b62a082734
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains a link farm pointing to numerous compromised websites, likely intended to redirect users to malicious content. The file's structure and embedded URLs suggest it is part of a phishing campaign or a distribution vector for further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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 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://cructi.ru/uplcv?utm_term=how+to+see+someone%27s+deleted+tweets
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160984bde9c2fa---zodegavubitininunu.pdf
    • http://asirakademi.com/resimler/files/fejikokefakuzujimurotuwo.pdf
    • https://ooo-kenk.ru/userfiles/file/zesujusesonevowusilawobi.pdf
    • http://thepnguyentran.com/media/ftp/file/zizigazotipiduzezewo.pdf
    • http://bodymindspiritconnection.org/clients/5/53/53f1eac0d8ee32431a47b4e1af774f29/File/61605025277.pdf
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/2ee4de8441337a68ab424ca820f8b191/weziro.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2122905add---98723614132.pdf
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/40279279676.pdf
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/hlockdk7eean8jaadbp2t6e2th/80644578835.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1b631d72a7---1425636219.pdf
    • https://adreshosting.com/calisma2/files/uploads/fezuwakupid.pdf
    • https://thuaphatlaihoanghuy.com/uploads/files/10273365441.pdf
    • https://www.expoagrogto.com/wp-content/plugins/super-forms/uploads/php/files/h7niddraq7lg0jup0tom766nt4/rasulupedobanifukuro.pdf
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/1bsnvp8bgk72nc35fh2kkl25r5/lasinixufujarusi.pdf
    • https://www.spreefahrten-berlin.de/wp-content/plugins/super-forms/uploads/php/files/lftnmlbppg1cvjcldohe4065n8/bakexutelixizowidobokeda.pdf
    • http://absolutelyneon.com/userfiles/file/pevajufolakidal.pdf
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0484213b3f---sovazetolivoz.pdf
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/76keaqq12j9j4crd86pej7di57/mexusuj.pdf
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609913d46785b---pokitosuzawob.pdf
    • https://fultoys.com/userfiles/gujakunusuxeromofalivij.pdf
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1d200bf8b---kabug.pdf
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/160c752449e6a9---51596066767.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011d68.bin
a0e745933f26f27e752f919b6e7662eb970f711c3157d07c3fa78a474e5bd752
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D68 18564 bytes
font_01_sfnt_off00014dff.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14DFF 16792 bytes
font_02_sfnt_off00016616.bin
2530ef0eceae6242a734cd0a69e677ff3e3d3b46dc257468c720afc14b9272e0
pdf-font-stream PDF embedded font (sfnt) at offset 0x16616 10164 bytes