Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ff0f4577a7757fe…

MALICIOUS

PDF

85.6 KB Created: 2021-07-04 20:21:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 26b45281efae2de1e5730dfc168e374c SHA-1: 0d59649a2e107b23c49a72a5bf4ccc0316368fce SHA-256: 4ff0f4577a7757fedf63c175628573e15ca96fa464d9d7d24d4f724cfa983d64
156 Risk Score

Malware Insights

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

This PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of links, many pointing to PDF files hosted on potentially compromised CMS upload directories, suggesting a link farm or SEO poisoning tactic. The document body is heavily obfuscated and unreadable, providing no direct user-facing content, but the presence of numerous external links indicates a redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://auto-spec.ca/fck/file/fegepexeviginozurili.pdf In PDF document text
    • https://leuphuotcamap.com/uploads/image/files/tupumuk.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071b52dacb94---satokiwuku.pdfIn PDF document text
    • http://www.nowsingapore.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/16098eb6f35593---10378759712.pdfIn PDF document text
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/c187iguj9na1a54a47gq7enu2m/67068556949.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608fee3dd6ede---joruvif.pdfIn PDF document text
    • http://klick-tipp.info/ckfinder/userfiles/publics/files/58935566300.pdfIn PDF document text
    • http://hoangduy.vn/vn/files/11666944871.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3c493c70cb---kigajewujaligopajeteviza.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/2ae7ea5c4b16785bd24ea515c488b1de/gaxuxonikomawes.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9dd33abb2---paliraxedun.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/1607fb87d90533---mozitojovusavonetatusiw.pdfIn PDF document text
    • https://aartipalette.com/userfiles/file/juwiveriwulimolerapal.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608037ec6e86b---59394626278.pdfIn PDF document text
    • http://odpadykj.cz/UserFiles/File/48116882739.pdfIn PDF document text
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/ce3da2f564d3e2b176a9ce636bf6bb61/newila.pdfIn PDF document text
    • http://arcomproltd.com/userfiles/file/88593804722.pdfIn PDF document text
    • http://canyonoaksmtg.com/~duckdi5/canyonoaksmtg.com/content/file/pezaw.pdfIn PDF document text
    • http://robertfeinberglaw.com/images/edit_images/file/tiguminewawopamonitetefix.pdfIn PDF document text
    • https://art-lamps-rali.eu/files/file/3300567575.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606f14695fb17---zimokuxusojalekolex.pdfIn PDF document text
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/cc0a5382846a1b5e1ca76343b27726f6/pumivenezigikisagedu.pdfIn PDF document text
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/e5f4cc3411c8892bf52ba0fcfde0925b/saruguzefinaxesewo.pdfIn PDF document text
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f1e6b90b4c---81876194518.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=temperate+mixed+forestPDF 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_off0000ec97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC97 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000104a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104A9 16560 bytes
SHA-256: 586aea38edb5e9915568fb2abb1d4d129181344ecc2310d9019c9f3651de175a
font_02_sfnt_off00012f90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F90 10572 bytes
SHA-256: 3dfe58bfa9ee0a75b9b56f12d8ce47a36ed178eb25e7348b749f17912395d5df