Malicious PDF — malware analysis report

Static analysis result for SHA-256 9d45f51b928444bf…

MALICIOUS

PDF

83.9 KB Created: 2021-09-11 09:12:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 84f73463d41755957e8c8b0030bac8de SHA-1: e2a3c3d0a08299848fc73698ee4a3f4d8525ce25 SHA-256: 9d45f51b928444bfab546cfcbb8b10c49ee2cd7dd74ac2ef309161b1cff04238
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged as malicious by both ML classifiers and ClamAV. It contains numerous embedded URLs that point to various domains, many of which appear to be disposable or compromised hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document is structured as a link farm on disposable hosting, suggesting an attempt to drive traffic or distribute malicious content. The presence of a link to a WordPress upload storage further supports this. No scripts were extracted, but the primary attack vector appears to be directing users to malicious external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://synerhu.ru/uplcv?utm_term=index+of+sherlock+s04 PDF link annotation
    • http://unseretochter.com/images/file/tofevifafepinoforol.pdfIn PDF document text
    • http://jutaek.humenia.com/upload/userfiles/2021/09/files/210909124428.pdfIn PDF document text
    • http://www.coverseg.com/uploads/ckfinder/files/27583459489.pdfIn PDF document text
    • http://mottaing.eu/userfiles/files/93456543191.pdfIn PDF document text
    • https://bisleriuber.genefied.co/ckfinder/userfiles/files/gufedubiwudoz.pdfIn PDF document text
    • http://ky-auto.com/uploadfile/files/xegubaxi.pdfIn PDF document text
    • http://www.jobibon.com/admin/userfiles/file/wusajanoweropuxajat.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b0d3dc488a---37391211463.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/161390faa9da6a---37197826331.pdfIn PDF document text
    • http://veitali.com/upload/files/xiwironomapem.pdfIn PDF document text
    • http://www.mamafoundation.cz/ckfinder/userfiles/files/70509564982.pdfIn PDF document text
    • https://optimustelecoms.com/ckfinder/userfiles/files/pewadirowivitesoj.pdfIn PDF document text
    • http://88cpap.com/userfiles/files/21034105789.pdfIn PDF document text
    • http://onlinepravenconsultant.com/uploads/wysiwyg/files/fegofifazigizubogu.pdfIn PDF document text
    • https://phuketwebstudio.com/ckfinder/userfiles/files/juxagatugifigarove.pdfIn PDF document text
    • https://taucaotoccatba.vn/images/news/files/58892794705.pdfIn PDF document text
    • http://magnumprint.ru/upload/files/wapetob.pdfIn PDF document text
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613c0c5db245c---kumifuxasenen.pdfIn PDF document text
    • https://vresponse.net/userfiles/file/44251325516.pdfIn PDF document text
    • https://weeb.nu/userfiles/file/zanebufex.pdfIn PDF document text
    • http://tauben-buchmeier.de/kleinberliner-schuetzen/userfiles/files/ruxet.pdfIn PDF document text
    • http://budapesticukraszdak.hu/userfiles/files/77548457449.pdfIn PDF document text
    • http://ssaisarang.com/ckfinder/userfiles/files/87529394582.pdfIn PDF document text
    • http://e-baze.lv/images/site/file/43765487638.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_off0000e015.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE015 19968 bytes
SHA-256: 47c2ab6f4bcac020c19fa69703f1fd211b6e6228f46b841c137d9fdfc0af918b
font_01_sfnt_off000111d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111D7 10564 bytes
SHA-256: db5923acc7372e407db6bd1e9f59b1d6b5ab27f03ad8b288fc2a3f714ad4419c
font_02_sfnt_off000129e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129E6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1