Malicious PDF — malware analysis report

Static analysis result for SHA-256 fbb540716cd40b1c…

MALICIOUS

PDF

80.2 KB Created: 2021-09-18 01:48:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 918a1c80fc85b8a4bb783651ae69c559 SHA-1: 98ddaa161300bad888e00d868ce75f2f0f6d44e2 SHA-256: fbb540716cd40b1c3bbbdbb599c146c67aedb9ac8dd8facf35dfc1ebd7a74efc
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous URLs, many of which are hosted on compromised WordPress sites or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 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://ketchas.ru/uplcv?utm_term=temple+run+2+for+pc+download+windows+7 PDF link annotation
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142416160527---8878422732.pdfIn PDF document text
    • http://shepardinteriordesign.com/rw/upload/file/21279836161.pdfIn PDF document text
    • http://locnuocvietmy.com/Images_upload/files/legewira.pdfIn PDF document text
    • http://ozdoby-betonowe21.pl/Upload/file/vinemusilokavalokelabi.pdfIn PDF document text
    • https://atcotourismtravel.com/userfiles/file/6305577128.pdfIn PDF document text
    • http://cbstav.cz/file/funugidisorupudujijin.pdfIn PDF document text
    • http://mgbig.com/upload_fck/file/2021-9-8/20210908125415517831.pdfIn PDF document text
    • http://robertfeinberglaw.com/images/edit_images/file/bepowikanafijobube.pdfIn PDF document text
    • http://fueandhair.com/userfiles/files/vunobofeletavo.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/1ffe46e2f5c7e859e4c1337a037a7e39/zomipudak.pdfIn PDF document text
    • http://all-premium.com/user_file/files/zizoduk.pdfIn PDF document text
    • http://scissortailfarms.com/wp-content/plugins/formcraft/file-upload/server/content/files/161346c807175c---sovuwogosojitez.pdfIn PDF document text
    • https://dolupin.com/calisma2/files/uploads/lorazoxudo.pdfIn PDF document text
    • http://titusauto.hu/kepek/file/39213711859.pdfIn PDF document text
    • http://tagsu.com/attachments/fckattachments/file/jidigaliwawarukuwebuw.pdfIn PDF document text
    • https://gymlesgeants.com/upload/editor/file/gimowulijevitekotu.pdfIn PDF document text
    • http://ipllaser.in/uploads/kigaxovenubinajuzali.pdfIn PDF document text
    • https://stop-remont.ru/ckfinder/userfiles/files/dekexuriv.pdfIn PDF document text
    • https://musikkursus.dk/userfiles/file/27289988902.pdfIn PDF document text
    • http://www.drivingschool-brno.cz/files/files/raboxemoleni.pdfIn PDF document text
    • http://alltechsro.cz/files/96441534331.pdfIn PDF document text
    • https://luxesystem.site/js/ckfinder/userfiles/files/jogemo.pdfIn PDF document text
    • http://terwaarde.be/ckfinder/userfiles/files/99378236174.pdfIn PDF document text
    • 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_off0000d5e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5E7 11004 bytes
SHA-256: fd85e3ed6d1b012531816e117569782225241c2f11fba203526b90018c813051
font_01_sfnt_off0000ef8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF8D 17076 bytes
SHA-256: 6da7e106a539c86e59413a06d174dc0415f39113760ee12cf3afe12bb50c43e3
font_02_sfnt_off00011b3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B3F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1