Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7a4b8f54f4f6d22…

MALICIOUS

PDF

84.3 KB Created: 2021-09-02 20:17:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 6655ecd2aa11e61421d2d6f900b2449a SHA-1: 4d823d7950e5bba6360d468e8f54a8d4a2689473 SHA-256: a7a4b8f54f4f6d2253ca049ffb89206b27ae35a33279d1aa888b87f1922347f5
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to compromised CMS uploads and disposable hosting domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ca378666b2---balipejetaroval.pdf In PDF document text
    • http://pololanna.com/user_img/files/kakidukonu.pdfIn PDF document text
    • https://golf-tout-terrain.com/publish/page/file/lowumobuzelowaxusiluwoko.pdfIn PDF document text
    • http://hferrynetworks.com/FileData/ckfinder/files/20210801_23A28F5D290BE786.pdfIn PDF document text
    • http://happy-land.hu/editor_up/xirijibivovalakujekaba.pdfIn PDF document text
    • https://eirai.org/editor/ckfinder/userfiles/files/ruwagadowizez.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca830732b6---71271225192.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16080faa686fc0---tipirub.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/8957caec652c0f13ea05d29f8948d70a/43559383562.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/16073ac10c264f---bagumasifabukukupeje.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160873599dacde---xokewabafazelujupu.pdfIn PDF document text
    • https://iohrp.org/f_files/files/91132738788.pdfIn PDF document text
    • http://yaan121.com/uploads/files/202108201746401925.pdfIn PDF document text
    • http://kath-kiga-bw.de/bilder/berichte/file/61672868044.pdfIn PDF document text
    • https://bhavanarayanaswamy.org/userfiles/file/40291174112.pdfIn PDF document text
    • https://synersys.fr/contenu/file/91401839534.pdfIn PDF document text
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7677c01ee1---19999256343.pdfIn PDF document text
    • http://shahgrp.com/uploads/33058966939.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/160733f5807719---42493730327.pdfIn PDF document text
    • http://ecompletecontact.com/ckfinder/userfiles/files/rukutiluxakoxuxupubakije.pdfIn PDF document text
    • http://host.keraladreamhomes.com/~viswabrahmathach/admin/fckeditor/editor/filemanager/connectors/php/userfiles/file/wuwukokisaz.pdfIn PDF document text
    • https://fratellifurloni.it/file/gadojosutuvomusakudofoxo.pdfIn PDF document text
    • http://girc.ncue.edu.tw/ckfinder/ckfiles/files/majigozupijosanimuzo.pdfIn PDF document text
    • http://westfallassociates.com/documents/file/jorilibesazu.pdfIn PDF document text
    • http://www.apsetedavisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3bf9c01ed---dutakedikijidurez.pdfIn PDF document text
    • https://thic.muki001.com/plugin/ce1/ckfinder/userfiles/files/jewekotifusabi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=seussical+jr+score+pdfPDF 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_off0000e53c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE53C 10716 bytes
SHA-256: 29a256371c4c0bfe9a14ecaa3fb25696812a32b5789e28ed6b34df68f8c194fc
font_01_sfnt_off0000fde4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDE4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000115f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115F6 17736 bytes
SHA-256: 62def3cf6236ba3484ffb93cb9ed2e4bd0faefe7f435380d8b5eed4c175749e7