Malicious PDF — malware analysis report

Static analysis result for SHA-256 e33bec4f58afb42e…

MALICIOUS

PDF

91.7 KB Created: 2021-07-13 15:03:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: e58beb28585e9d131854eadeb31e240e SHA-1: 49668eda9cc5274bce6ae0d61c530ba4083a80af SHA-256: e33bec4f58afb42e40033ad81fc38bcd682f6a68efee8529993988a3fb84dd7e
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple links to external URLs, some of which point to compromised WordPress sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution. The embedded JavaScript is a common technique for executing malicious code or redirecting users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

Heuristics 8

  • 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 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://empylean.com/wp-content/plugins/super-forms/uploads/php/files/r5l8a60m30hb682e5lsbmvupur/93614227869.pdf In PDF document text
    • http://classicalgardenfountains.com/uplds/file/zipuwilifaloruzux.pdfIn PDF document text
    • http://ateliergermain.net/sites/default/files/file/nimobosadowokerigepuge.pdfIn PDF document text
    • https://www.demetagras.com/wp-content/plugins/formcraft/file-upload/server/content/files/160719e4acc4a6---benadufewitevixonudifefu.pdfIn PDF document text
    • http://bkht.vn/userfiles/file/33534286192.pdfIn PDF document text
    • http://www.esthemed.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160bffe0f97f20---sododoluveraze.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608c912f554de---79171497593.pdfIn PDF document text
    • http://www.annaleehuber.com/content_files/file/40621001608.pdfIn PDF document text
    • https://farmaciasacoor.com/site/upload/file/xivofugesav.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/9a784ff322562ad5038015c2adfc017d/19804032497.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/8eab535b617346ccdd6bd38cc09b881a/vefugifipeko.pdfIn PDF document text
    • http://businessplan-capalpha.eu/mbp/upload/images/images/upload/ckfinder/85318500844.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079668fbc06a---vazove.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/66cdd1da45093ff9f727185b39e4b13b/tonejebifa.pdfIn PDF document text
    • http://ediljolli.com/userfiles/files/jerezil.pdfIn PDF document text
    • https://vandolderskb.com/images/usr/gilerebisunewadozav.pdfIn PDF document text
    • http://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f73c5b716d---tebig.pdfIn PDF document text
    • http://musclecar-taps.com/js/upload/files/kepefopepigodeku.pdfIn PDF document text
    • http://www.derbysignandgraphics.com/uploads/file/butodibuvuperexotu.pdfIn PDF document text
    • http://cymrozgreatdanes.com/clients/1/1a/1a407d8ccac5525c71aaafb6b4664123/File/gerutera.pdfIn PDF document text
    • https://realestateconnect.pro/wp-content/plugins/super-forms/uploads/php/files/delet6vdg21qf4cjetkheupkf7/10781925637.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160c33cc865cfd---853566319.pdfIn PDF document text
    • https://obermeyer-modemarkt.de/upload/file/20976256176.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/03a9dad7c51f1419350acbe5c57ae4c0/184442441.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/04cbfbf0ab4703b799cc2a45b3a2eb69/25508831985.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=baby+poems+in+englishPDF 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_off000102d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102D7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011aee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AEE 10808 bytes
SHA-256: b3bdf71630c2b9c3e15d0e934dbfa440312250e2d9cd5eda7820712da27e3424
font_02_sfnt_off00013371.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13371 17528 bytes
SHA-256: 26d759c3f55147c55544a3c713be12b7c2cefd8619a7d776037ed26156b7c9fa