Malicious PDF — malware analysis report

Static analysis result for SHA-256 d2875e4b1ef54da2…

MALICIOUS

PDF

79.6 KB Created: 2021-09-13 23:07:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: f814b8bfc114e16677e64057fec9b544 SHA-1: 2aea47515edfbb804056df0ddbacb8616c61ab03 SHA-256: d2875e4b1ef54da2b7b334e1b57031c295a15c7840ff804eaed19c96bc50d87e
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised WordPress sites and disposable hosting, suggesting a phishing or malware distribution scheme. The embedded URLs, despite some being marked benign, contribute to the overall pattern of directing users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://np-laser.com/upload_fck/file/2021-9-2/20210902053050104697.pdf In PDF document text
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c7cc151ceb---50865938124.pdfIn PDF document text
    • http://safires.cz/ckfinder/userfiles/files/48394683119.pdfIn PDF document text
    • http://bushurov.ru/images/files/81468338746.pdfIn PDF document text
    • http://fueandhair.com/userfiles/files/zuzitukigoso.pdfIn PDF document text
    • https://bilegt.mn/userfiles/files/1025461544.pdfIn PDF document text
    • http://scea.edu.mn/ckfinder/userfiles/files/88872370022.pdfIn PDF document text
    • http://xn--54-dlcdkamdj4btild5b.xn--p1ai/ckfinder/userfiles/files/zofafuzuvulozokagu.pdfIn PDF document text
    • http://optikametuje.cz/userfiles/file/3854593462.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161303c8663775---zonikitafixibuvun.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/64b69ae36cb3bc0affa17afc383ad5b8/zurelatepijafokeretison.pdfIn PDF document text
    • http://www.grupoaccs.net/ckfinder/userfiles/files/dekumama.pdfIn PDF document text
    • http://grupopiscis.com/upload/files/71309273753.pdfIn PDF document text
    • http://noclegsosnowiec.pl/eurostyl/photos/file/lurabu.pdfIn PDF document text
    • http://seoaudytor.pl/userfiles/file/47779373850.pdfIn PDF document text
    • http://homokkepek.hu/editor_up/53138808316.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/161327f7fc542b---mipodixurewirisonatoku.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/16137644b5caad---40983423651.pdfIn PDF document text
    • http://stroi-sistema.ru/img/6382454187.pdfIn PDF document text
    • https://totspotdaynursery.co.uk/ckfinder/userfiles/files/xaxufoxe.pdfIn PDF document text
    • http://nepodoshlo.kz/ckfinder/userfiles/files/90448273626.pdfIn PDF document text
    • https://australiancaravancentre.com.au/application/third_party/ckfinder/userfiles/files/27191527956.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=advanced+excel+pdf+downloadPDF 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_off0000d258.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD258 17976 bytes
SHA-256: 07ccb3a715f274313cc34b4fc1281f79024a8e6ac47ee6659d330b6f94617ac4
font_01_sfnt_off0001012d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1012D 10388 bytes
SHA-256: 4d9a85fc2f9212894583abfd693c46bf2d683975fc5f303bd775321b6a353d3e
font_02_sfnt_off000118e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118E9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1