Malicious PDF — malware analysis report

Static analysis result for SHA-256 0db1bf358b821890…

MALICIOUS

PDF

72.5 KB Created: 2021-09-29 13:49:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 0274d8a0d00b1e55525b6e35f7aa81aa SHA-1: 8af6b138c8a36521db4eddbe01faa0f113d87f01 SHA-256: 0db1bf358b8218903c8155f2afd3ad1d26f72cf9d14e415f58000cda33fe91e1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to other PDF files hosted on potentially compromised websites or disposable hosting. This behavior is indicative of a link farm, likely used for SEO poisoning or to distribute further malicious content. The ML classifier and ClamAV detection strongly support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 http://tt-ural.su/admin/ckfinder/userfiles/files/3529813922.pdf In PDF document text
    • http://shopsuathientu.com/uploads/userfiles/file/doluvefifabipude.pdfIn PDF document text
    • http://vaonhaphatphap.com/images/uploads/files/sopatosakar.pdfIn PDF document text
    • http://darslaska.org/ckfinder/userfiles/files/ruwejafusal.pdfIn PDF document text
    • https://safewatersolutions.in/ckfinder/userfiles/files/16936158883.pdfIn PDF document text
    • http://webcertain.ca/contentupload/fckeditorUploads/organization_/file/wojevetazapawivulagapani.pdfIn PDF document text
    • http://maekuangudomthara.com/ckfinder/userfiles/files/45926955099.pdfIn PDF document text
    • http://tea-ra.com/user_data/upload/save_image/files/rexasanewap.pdfIn PDF document text
    • http://directopinion.biz/uploads/FCK_files/file/fokababedagopexawux.pdfIn PDF document text
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/9988c5d8cedcb460e29e3c1daa2a8640/30464392390.pdfIn PDF document text
    • http://donghozibistore.com/luutru/files/suretozilav.pdfIn PDF document text
    • https://inprovitcaribe.com/ckfinder/userfiles/files/18163456031.pdfIn PDF document text
    • https://apelhijau.com/contents/files/25198906998.pdfIn PDF document text
    • http://zssadkowice.pl/pliki/vogaviwuvi.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161319c1f696c1---benujabudepafabifej.pdfIn PDF document text
    • http://cosmik-kinoteatr.ru/sadm_files/fasasagekebosugozaxevav.pdfIn PDF document text
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161485532491f5---99640207707.pdfIn PDF document text
    • http://www.otevrenysklep.cz/ckfinder/userfiles/files/jupebupifi.pdfIn PDF document text
    • http://gorisum.net/fckeditor/upload_file/file/65938783969.pdfIn PDF document text
    • http://www.pantonerestauri.com/ckfinder/userfiles/files/9823831078.pdfIn PDF document text
    • http://torby.kbo.pl/ckfinder/userfiles/files/55199495916.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=harvest+moon+seeds+of+memories+apkPDF 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_off0000b3b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3B6 10760 bytes
SHA-256: 63b1744ff55aed24483848036aaf7886a5a356601c76cd9dee51ce05cb4ccf47
font_01_sfnt_off0000cc72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC72 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e484.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE484 18868 bytes
SHA-256: 946b2299defa26c8db6b6575ba2843d4969d288fe001d6b003f3b0d862eb98cb