Malicious PDF — malware analysis report

Static analysis result for SHA-256 b59cf1868d99c91e…

MALICIOUS

PDF

85.4 KB Created: 2021-09-06 17:05:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: adbd4b23c04c6e3039c9108e6919540c SHA-1: 8a2e26eec785ced7b531d7b935a53f8fe30c7f89 SHA-256: b59cf1868d99c91ecca1d6608de04cb0448d2dbba138085914154f1a2f43b88e
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, pointing to numerous external URLs hosted on compromised WordPress sites and disposable domains. These links are likely used to distribute phishing content or download further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 6

  • 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 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 https://krisoc.ru/uplcv?utm_term=dbt+jrf+syllabus+pdf PDF link annotation
    • http://abwessex.com/uploads/files/gajutogilebajimewixuw.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/3qb0vuoev3qkf31fjolii2te76/30406625696.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608b4aa0549e6---muxoxefebatinijigofafaj.pdfIn PDF document text
    • http://centreforeffectivecoaching.com/media/file/vitil.pdfIn PDF document text
    • http://ryanoomen.nl/uploadimages/files/87901956279.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/rabako.pdfIn PDF document text
    • http://granitemountainranch.net/userimages/zalabiwipowamopu.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/84ce626dac26dea1b35c137495e7ea5b/72453619873.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/43310837099.pdfIn PDF document text
    • http://cableesmaltado.com/d/files/87418211806.pdfIn PDF document text
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1eb43818e2---86163616549.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/12163583410.pdfIn PDF document text
    • https://bjsteelvietnam.com/upload/fck/file/genigufa.pdfIn PDF document text
    • http://metalltechnik-kutschi.at/gokukawezegimevixuduwute.pdfIn PDF document text
    • http://shiny-baby.com/fileimage/file/piduvatatiwa.pdfIn PDF document text
    • http://keysrotary.com/clients/d/da/da683cbc30bfd632b0b364d14bdd38fd/File/13428677202.pdfIn PDF document text
    • https://doellefjelde-mussemarked.dk/images/newsmail/file/54302548670.pdfIn PDF document text
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/sio3c6jo7oatmi9vtuqpbr9gil/62562995942.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160c8833ea07cc---dotugegadozut.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160ddead12edde---fawimoxewoxosulowogixuz.pdfIn PDF document text
    • http://www.halpellet.hu/userfiles/files/76173758427.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/fdp49nrb42doruj69u8kig3920/84239674507.pdfIn PDF document text
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b87abfca240---fimorotigowid.pdfIn PDF document text
    • https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/6559679ba0d4a0d83d0d8d1d958b1d1b/dotaxedesikefunaja.pdfIn PDF document text
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9f4a47a16d---fofutukuzasemivase.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4aa8b46b76---79537385800.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_off0000e8ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8CA 10528 bytes
SHA-256: 452be9bd06326816bf5eb3299acae8e52362e57515518ec368578a12d55feabc
font_01_sfnt_off000100b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100B8 18160 bytes
SHA-256: 87bbdd826d57ef96a913c99dc6820e56d6e24cc147571bb99aaef3a0dd39a066
font_02_sfnt_off00012feb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FEB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1