Malicious PDF — malware analysis report

Static analysis result for SHA-256 40ee90b399c0c25d…

MALICIOUS

PDF

81.3 KB Created: 2021-09-18 22:55:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 31bfe29160df24a5d7364a558b98aba7 SHA-1: e7c60ac5a7a4cf0fe101aa6acae5775e677332fa SHA-256: 40ee90b399c0c25d787d3acfaf57f120382cc67a660092dd19d0f206a7de07ba
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm with numerous URLs pointing to various domains, many of which appear to be compromised WordPress sites. The primary purpose seems to be redirecting users through these links, likely to a phishing page or to download a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 https://coretry.ru/uplcv?utm_term=the+house+that+jack+built+2013+full+movie PDF link annotation
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613257afbf37b---lulakufiraretis.pdfIn PDF document text
    • https://www.groupe-coelho.fr/ckfinder/userfiles/files/valimisezafid.pdfIn PDF document text
    • http://prestizhstroycompany.ru/SITE/files/editor/file/94676433231.pdfIn PDF document text
    • http://greddy.com/admin/common/ckfinder/userfiles/File/23866411810.pdfIn PDF document text
    • https://ariaparvaz.com/basefile/ariaparvazcom/files/34019779964.pdfIn PDF document text
    • http://bowie.abwingsmd.com/uploads/files/99136022053.pdfIn PDF document text
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/f3fmcn9knk3fat1ula2dfa6t62/78277478748.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/67044864115.pdfIn PDF document text
    • http://onnetsolution.in/userfiles/file/sigosutepi.pdfIn PDF document text
    • http://elcampoeco.org/FCKeditor/file/38643633160.pdfIn PDF document text
    • https://www.baust.edu.bd/app/webroot/ckfinder/userfiles/files/tufudakejuvowimega.pdfIn PDF document text
    • http://hkacca.com/userfiles/40446946231.pdfIn PDF document text
    • https://ctners.com/ckfinder/userfiles/files/wajugujanev.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/67f25c73d18002731921fa5e6ce69853/56471969971.pdfIn PDF document text
    • https://stdtekstil.com/upload/ckfinder/files/63033691507.pdfIn PDF document text
    • http://aryajob.com/user_upload/file/86000161935.pdfIn PDF document text
    • http://opgzvh.hr/upload/file/mazezilofowodumobage.pdfIn PDF document text
    • https://xn--80apefbdm9ah5g.xn--p1ai/userfiles/78256510943.pdfIn PDF document text
    • http://www.its-dph.cz/admin/fckeditor/editor/userfiles/file/geriwitili.pdfIn PDF document text
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/ef9a7904d8e194609eb36e340b0c21bf/pobajupi.pdfIn PDF document text
    • https://autopits-directo.migrupoq.com/ckfinder/userfiles/files/95907916921.pdfIn PDF document text
    • http://gyndoktors.de/ckfinder/userfiles/files/94983128857.pdfIn PDF document text
    • http://bsl-trans.ru/admin/ckfinder/userfiles/files/4586162923.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_off0000d872.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD872 17300 bytes
SHA-256: d961798876961020b99e397d87bf94d7aa274d2e1bf372299c39fb0638dfa237
font_01_sfnt_off00010522.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10522 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011d39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D39 11352 bytes
SHA-256: b5dd6359b47cb8dd525ce55f7f32e51eb50bc19475f1b57c899ffd77c4edac71