Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac38f842f7fa31b8…

MALICIOUS

PDF

73.0 KB Created: 2021-06-06 12:20:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-14
MD5: 62d3b761c0f1bea4b88be050dd9ebd59 SHA-1: 366a5c42242c8ae702ecff1f31826c9b3b068373 SHA-256: ac38f842f7fa31b87d0bed6174105d94f81cca6c374af4b8f3f251d20506c6d7
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to various compromised websites, disguised as a YouTube downloader. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it's designed to redirect users to malicious content, potentially exploiting PDF vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://synerhu.ru/uplcv?utm_term=y2mate+youtube+downloader+2021 PDF link annotation
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1608c3634d96bc---36979728647.pdfIn PDF document text
    • https://brandonsmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/d8b2ieoajnp786usmfouag4k97/15832122614.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093e596c802e---49899528075.pdfIn PDF document text
    • https://t2sc.me/userfiles/83276697487.pdfIn PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/1609d17c0bc313---fusude.pdfIn PDF document text
    • https://nikosdimos.gr/userfiles/file/87429249270.pdfIn PDF document text
    • https://cgeminfos.ma/upload/file/gaxelafazotufenuvubotuduj.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/xojelap.pdfIn PDF document text
    • http://www.sandzthabapanel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16073435da6de2---89982131351.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072b0941277d---vonewuvako.pdfIn PDF document text
    • https://reflexlighting.com/wp-content/plugins/super-forms/uploads/php/files/9396e849259aff0a6d6bbe7a99af1451/11646656596.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/601b2b3d3c8731555e013a1b45bee6c5/164598031.pdfIn PDF document text
    • http://www.circoloaletrium.it/wp-content/plugins/formcraft/file-upload/server/content/files/160aa78f9483de---52611216738.pdfIn PDF document text
    • https://roweryelectra.eu/app/webroot/uploads/file/16198663331934.pdfIn PDF document text
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/8ns45t3pltfb0vo8f2vf1isslb/soleku.pdfIn PDF document text
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/erko3dcsdn8ogl0ijvmi13uen3/lonijisisenazefuzubigoz.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d246.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD246 5248 bytes
SHA-256: cd481bd5d2a0b20ce99e1122ec7e593cfa71da9bff3a0ac3b80ae82a4928e839
font_01_sfnt_off0000e413.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE413 11196 bytes
SHA-256: 37b93287b7d68ca12f03ab837bb8a4a75678ae0708e61ccbe1c44b6f57cb5218
font_02_sfnt_off000108fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108FA 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333