Malicious PDF — malware analysis report

Static analysis result for SHA-256 7826788a4abb7b15…

MALICIOUS

PDF

77.8 KB Created: 2021-09-19 01:23:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: fb2c63406509697e4c5aa83fd4c4b9f5 SHA-1: 2143abaec777eb02f8900b497102bad070409d9c SHA-256: 7826788a4abb7b15f4d3a88eb9ae147e084af757dc68a4ea08506d36cd640149
126 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document is designed as a link farm on disposable hosting, with numerous distinct hosts and UTM parameters, suggesting a phishing or malware distribution campaign. While no scripts were extracted, the embedded URLs and the nature of the heuristics point towards an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://clinicscrm.com/img/files/ruzibuvoki.pdf In PDF document text
    • http://rentappli.com/tinymce/jscripts/tiny_mce/plugins/phpimage/phpimage/upload/images/file/86500040302.pdfIn PDF document text
    • https://defi128.com/userfiles/files/21782016013.pdfIn PDF document text
    • http://vekosgroup.ru/userfiles/file/45889675298.pdfIn PDF document text
    • http://tao-ssct.org/data/upload/file/38786970762.pdfIn PDF document text
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/bbc9b44d02c7b35cb5ae668b5f2540a5/riwuworalovenavotedumuk.pdfIn PDF document text
    • https://macintosh-szerviz-javitas.nuttydog.hu/ckfinder/userfiles/files/3288515508.pdfIn PDF document text
    • http://tykhchem.com/upload/files/44237853555.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/161421f7218a3c---xepaxiwalu.pdfIn PDF document text
    • http://rrmkaryacollege.org/rrmkarya/userfiles/file/zugiwafazewagubivivada.pdfIn PDF document text
    • http://mobitransjogja.com/files/damelajag.pdfIn PDF document text
    • http://monteconsultants.com/image/upload/File/xipiwuzokapiripaleviwuda.pdfIn PDF document text
    • http://ballarioarchitetti.eu/userfiles/files/69938803411.pdfIn PDF document text
    • http://hieuchuan.com/upload/files/gisorusugomusumek.pdfIn PDF document text
    • http://fgsconsulta.com.br/ckfinder/uploads/userfiles/files/jirifexitepirerap.pdfIn PDF document text
    • http://sowa-architekci.pl/userfiles/files/4768485651.pdfIn PDF document text
    • http://wsm.hk/images/files/68240698892.pdfIn PDF document text
    • https://chandrakantmusicacademy.org/ckfinder/userfiles/files/96779074702.pdfIn PDF document text
    • https://greenbins.ca/ckfinder/userfiles/files/gapazetavugezinesoz.pdfIn PDF document text
    • https://underworldgear.com/admin/images/fckImg/file/6302912678.pdfIn PDF document text
    • http://innersolutions-uk.com/file/20546308841.pdfIn PDF document text
    • https://dyaa.club/uploads/file/95161318058.pdfIn PDF document text
    • http://autodilykanka.cz/cmsimple/images/file/difasuvebibulewagulobow.pdfIn PDF document text
    • http://gillsandgeckos.com/userfiles/file/23839438996.pdfIn PDF document text
    • https://tedvandergulik.nl/userimages/file/depewupotavulol.pdfIn PDF document text
    • http://pro-elec.ru/ckfinder/userfiles/files/97091452317.pdfIn PDF document text
    • http://www.bluefashion.cz/ckfinder/userfiles/files/40804565864.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=roblox+mad+city+codesPDF 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_off0000cb25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB25 10728 bytes
SHA-256: 9d5f01d2d8b74babb8a1b0322450ca8afbd0a7f0fffa43342b4a314a31bb76f5
font_01_sfnt_off0000e3dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3DC 17676 bytes
SHA-256: 72aac0659da5de4955ce9d6dfbce80ee68fc6ee5997c960fbc9ca35b64e46765
font_02_sfnt_off00011181.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11181 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1