Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef7bbe501d18b336…

MALICIOUS

PDF

79.8 KB Created: 2021-09-24 08:00:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c96e5b30ee6494591ad673ceef1df147 SHA-1: cab1a57169a4c756322c46b9ea2b0acbc1bfc9ef SHA-256: ef7bbe501d18b336aa76207d5c50be43e403409993f28d7fc50905ac8d53c8b2
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of embedded URLs and the nature of the heuristics suggest the document's primary purpose is to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 7

  • 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 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.
  • 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 http://www.predia.cz/userfiles/file/77490425500.pdf In PDF document text
    • http://nontaromclinic.com/ckfinder/userfiles/files/winibaxobuvevo.pdfIn PDF document text
    • http://p-energo.ru/content/file/sedofeguxat.pdfIn PDF document text
    • http://tatnhapkhau.com/ckfinder/userfiles/files/gipozizudoborosoj.pdfIn PDF document text
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/108ab537ebec7fdcc0020038de405a8d/70818524580.pdfIn PDF document text
    • https://www.barrau-philippe-sedeco.fr/ckfinder/userfiles/files/jugeset.pdfIn PDF document text
    • http://huyminhplastic.com/upload/files/saximaju.pdfIn PDF document text
    • https://postele-z-masivu.sk/ckfinder/userfiles/files/53907384340.pdfIn PDF document text
    • http://mimarathi.live/assets/ckfinder/core/connector/php/uploads/files/batir.pdfIn PDF document text
    • https://maviet.vn/upload/files/zaxumoguvojebaxe.pdfIn PDF document text
    • http://kubkao-kubpla.com/userfiles/files/desewesu.pdfIn PDF document text
    • http://phantasos.org/userfiles/file/54732021559.pdfIn PDF document text
    • http://hitmet.slektenkaas.com/bilder/file/deguxigovofara.pdfIn PDF document text
    • http://ornito-silesia.eu/userfiles/file/62862944873.pdfIn PDF document text
    • https://maintogelonline2.com/contents/files/47450773329.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/hd7dsbvj8ff7cp8886tcsfn574/janoramejuj.pdfIn PDF document text
    • http://krallarintavugu.com/upload/file/bopokananobabani.pdfIn PDF document text
    • http://budka39.ru/files/dapikebuxovulazexisakuga.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/t3rgd1lp52pvhci4ejn1f1780b/59378287081.pdfIn PDF document text
    • https://santevita-bg.com/ckfinder/userfiles/files/31001404674.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=wonder+woman+bloodlines+watch+freePDF 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_off0000d27f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD27F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ea96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA96 10960 bytes
SHA-256: 6deafb21aa321d8fe7604defbb4e9f9ab4966a252694603496ce2e4818851cb7
font_02_sfnt_off000103d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103D2 17812 bytes
SHA-256: 7d8d6b7ef52c985a981bc0946a0cbf4f8a36a0ebbfc6d35d0ebdc5c61dce81ec