Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b69d968e50470d2…

MALICIOUS

PDF

81.4 KB Created: 2021-09-03 02:50:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: dfb1c09482c6d0976bdf4f27a81b139b SHA-1: 07ac5a79cf87eb1860bb111b8bd013fb6aee92a4 SHA-256: 5b69d968e50470d2433ed7769d420203251ee9a99d1957c618ef0e8fdb857d0b
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm or phishing lure. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were directly extracted, the structure and embedded URLs are indicative of a phishing or malicious redirection scheme, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://synerhu.ru/uplcv?utm_term=free+printable+sight+word+worksheets+for+first+grade PDF link annotation
    • http://m2mus.ca/clients/b/b1/b1ca46fdb12d68e762e4a8b3318caec0/File/nigoxizu.pdfIn PDF document text
    • http://vidol.nl/userfiles/file/44886934361.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072f2e2018e8---juruwamezefasopomu.pdfIn PDF document text
    • https://cls-toronto.com/wp-content/plugins/super-forms/uploads/php/files/8f04f54a3bc7641ee9793642331fa7e1/39813682129.pdfIn PDF document text
    • http://hotechike.com/files/files/zezekupojogoxibe.pdfIn PDF document text
    • http://shoreluxurylimos.com/userfiles/files/17894874784.pdfIn PDF document text
    • http://cukiernia-waltar.pl/qcms/userfiles/file/ruxetunid.pdfIn PDF document text
    • http://bakoca.hu/files/file/85165810609.pdfIn PDF document text
    • http://hoteldazegliotorino.com/userfiles/files/pupuduloj.pdfIn PDF document text
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/e7e79712498f38bcba34bd4e88afeb0d/wudopori.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1611b89f94ebb1---gomuzagimilewi.pdfIn PDF document text
    • http://thessalonikiflights.com/files/files/mesagapugubuja.pdfIn PDF document text
    • http://toptoptraining.ru/img/upload/file/36089645724.pdfIn PDF document text
    • https://amadesafar.ir/basefile/amadesafarir/files/32211318605.pdfIn PDF document text
    • http://dui-antidote.com/images/userfiles/file/15339575685.pdfIn PDF document text
    • https://aadhaarretail.com/administrator/imagetemp/file/rozibupudesa.pdfIn PDF document text
    • http://cngwalk.com/fckeditor/userfiles/image/soweju.pdfIn PDF document text
    • https://gulfsupremesa.com/ckfinder/userfiles/files/miwifujusizalizedumirig.pdfIn PDF document text
    • https://www.ideaklinik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075d11bab475---42567868823.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/23t560acus86gitlitca7io91a/mexenitizatowonexudupe.pdfIn PDF document text
    • https://berbagiangka.com/contents//files/4118212759.pdfIn PDF document text
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/6ba74b0609ffac2dfacf787dbdd4200d/nemurekoto.pdfIn PDF document text
    • http://udmvdpo.ru/images/files/lakeze.pdfIn PDF document text
    • http://www.77ice.com/upload/files/3067833898.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_off0000d908.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD908 17572 bytes
SHA-256: 2c2213cb2d64a2bfb5367d81a0564dd660d6f2ecaebda40eb1b809d103f84052
font_01_sfnt_off00010637.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10637 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011e4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E4E 11072 bytes
SHA-256: 3bb9659e0a72976d882ae3e9347d82e8c2570b515b1a6dc1053cd6af1d0b3145