Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f5f10eab254347d…

MALICIOUS

PDF

82.9 KB Created: 2021-08-29 13:11:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: e6f5c2289e2740487246dd57f3d513ed SHA-1: 773610feed63c5680f05362e0c7e663e55d173eb SHA-256: 4f5f10eab254347dc8b5921ecd0c0381f0965ffa09bb69f94e51ff81dab9f9de
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests this is a tactic to distribute malicious content or phish users. No scripts were extracted, but the PDF structure itself is used to host a large number of external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://crewmak.ru/uplcv?utm_term=ps+command+in+linux PDF link annotation
    • http://seoaudytor.pl/userfiles/file/gatomu.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160ffc30475387---xapisivepivibufikub.pdfIn PDF document text
    • https://avenue102.com/uploads/file/91915729706.pdfIn PDF document text
    • https://gulfsupremesa.com/ckfinder/userfiles/files/sabemalumatazufawaz.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a6576f6d47b---46083656815.pdfIn PDF document text
    • http://cbestdesign.com/ckfinder/images_store/files/mimumudokapanoxepob.pdfIn PDF document text
    • https://agenciaboom.com/wp-content/plugins/super-forms/uploads/php/files/1pi77t6bkqg69umuc6qb8mk9k1/52710612861.pdfIn PDF document text
    • http://sutinlawkrabi.com/ckfinder/userfiles/files/34660236550.pdfIn PDF document text
    • https://mattress-leader.com/media/rupajofigobe.pdfIn PDF document text
    • http://www.almansori-ye.com/almansorifiles/files/vuvotip.pdfIn PDF document text
    • http://musicpark-live.de/userfiles/file/soleliniwaki.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-5-20/20210520121312403320.pdfIn PDF document text
    • http://matstravel.ru/userfiles/file/29314955829.pdfIn PDF document text
    • http://statewideroadservices.com/clients/879378/File/4166585193.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/ab7a1569967bd961b7f966c97db098de/dufafutuxovibetizem.pdfIn PDF document text
    • http://merrygoldholidays.com/ckfinder/userfiles/files/tanazugaxogesidafexufom.pdfIn PDF document text
    • https://autoteam.in/ckfinder/userfiles/files/89868022721.pdfIn PDF document text
    • http://ats-dz.com/userfiles/file/48525481578.pdfIn PDF document text
    • http://robertoantoniz.com/resources/original/file/60598975399.pdfIn PDF document text
    • http://www.pilartangguh.com/file/xalurafabakidefisuxediruk.pdfIn PDF document text
    • https://smg.bid/ckfinder_userfiles/files/mafuwu.pdfIn PDF document text
    • http://bsa-billiard.by/images_from_html_editor/file/83611108318.pdfIn PDF document text
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/1975ae6d6b8c307b0ef9ecbd6885440e/91789821978.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_off0000dca7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCA7 19008 bytes
SHA-256: 5b6ffa7b05f6d1a6b10fd1edcc6529755d977b9ea5149662b703f5d2cbeafc28
font_01_sfnt_off00010e61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E61 10404 bytes
SHA-256: f2d8c20b575dbdd95c0e7c6e7fdb89d982084858e4d6e2614aee9ab427cfe583
font_02_sfnt_off000125e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1