Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c28dcd3c64e383a…

MALICIOUS

PDF

68.8 KB Created: 2021-09-29 02:55:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 844fc9110676872d3f939d6fec89b47b SHA-1: e765efa53f5be0087e288dd4b363f0b5eab9644d SHA-256: 0c28dcd3c64e383ad80b6ea4620763325193d8c4d45d060c3fefdf7e60d8cbc0
126 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs, with one specifically identified as a link farm on disposable hosting, suggesting a phishing or redirection scheme. The PDF's structure and the presence of many external links point towards an attempt to direct users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://cructi.ru/uplcv?utm_term=albert+einstein+inventions+pdf PDF link annotation
    • http://reguitti-engineering.it/userfiles/files/97308292181.pdfIn PDF document text
    • http://chickenwild.com/upload/contents/images/images/rumaribekum.pdfIn PDF document text
    • http://schuetzenfest-hemeringen.de/ablage/userfiles/files/75872331757.pdfIn PDF document text
    • https://thehouseconcert.com/ckfinder/userfiles/files/jupakibilosapu.pdfIn PDF document text
    • https://wtmasonry.com/ckfinder/userfiles/files/2725685228.pdfIn PDF document text
    • http://challendor.com/fckeditor/upload/file/bofetatowes.pdfIn PDF document text
    • http://precisao.org/files/files/bafomivobikovosiga.pdfIn PDF document text
    • http://youngdongtec.com/userfiles/file/82611000314.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/34392974423.pdfIn PDF document text
    • http://aqcorth.specialty-match.com/upload/files/23835780005.pdfIn PDF document text
    • https://tbsva.org/Upload/files/20210921011050.pdfIn PDF document text
    • http://superfasttv.com/uploads/files/gabawe.pdfIn PDF document text
    • https://ural-aiti.ru/admin/ckfinder/userfiles/files/6153620105.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16153a266e23d5---fabiwujotokof.pdfIn PDF document text
    • https://perkunasstudio.com/uploads/files/202109152014509911.pdfIn PDF document text
    • http://kredoteka.ru/uploads/file/rifikiloz.pdfIn PDF document text
    • http://ylpcl.com/ckfinder/userfiles/files/wewodudewupag.pdfIn PDF document text
    • http://1hozain.ru/files/userfiles/files/97828858196.pdfIn PDF document text
    • https://stiff.pl/ckfinder/userfiles/files/bafimisirevezula.pdfIn PDF document text
    • https://ww170002.linebot.net/upfile/files/20210929052945.pdfIn PDF document text
    • http://obasekiestates.com/UserFiles/file/86316199067.pdfIn PDF document text
    • http://pc75.net/upfiles/file/1630722156.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/161363c97c6ef5---fuwuvobabitulefufegu.pdfIn PDF document text
    • http://kalmi.ru/upfiles/files/13059514010.pdfIn PDF document text
    • https://hunglivet.com/uploads/files/202109171325336572.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_off0000b101.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB101 10516 bytes
SHA-256: eba8432a48968367c1665419d7135e539f7cb8e03a750788b7305fd459246c9e
font_01_sfnt_off0000c8d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e0e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0E8 14784 bytes
SHA-256: 940de7cac81f23befa551bb2aac3eab3ee92570baf7447dc455553d044b4b421