Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a8b973ec37aff09…

MALICIOUS

PDF

71.6 KB Created: 2021-09-17 09:44:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 74d0365c480974b7e8c628b4d1e4afbf SHA-1: cb8ad9ad590bc91c865350f6c3727ff4a7e2b5d9 SHA-256: 5a8b973ec37aff093067060cb53fbaafb0156273bc7ad98d795bc3f2841ec0d6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to potentially compromised websites or disposable hosting, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery mechanisms.

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 https://irlanc.ru/uplcv?utm_term=desi+boyz+full+movie+online+123movies PDF link annotation
    • http://erdbau-rauch.at/fofunolofarisaximirutu.pdfIn PDF document text
    • http://businessdevelopmentcenter.pl/uploads/userfiles/files/dadadunufimaruloseso.pdfIn PDF document text
    • https://iqmuseum.mn/uploads/files/41495634792.pdfIn PDF document text
    • http://eortak.com/img/fck_temp/file/51395535370.pdfIn PDF document text
    • http://onsijsselstein.nl/userfiles/files/77066469832.pdfIn PDF document text
    • http://perila-vrn.ru/userfiles/file/40814642330.pdfIn PDF document text
    • http://belly.bpv.su/content/files/files/69196783847.pdfIn PDF document text
    • http://forglass.sk/userfiles/file/beridis.pdfIn PDF document text
    • http://klubbelgickychobrov.sk/editor_uploads/files/58106777073.pdfIn PDF document text
    • http://apsara.ru/userfiles/file/61819663053.pdfIn PDF document text
    • https://pinpointfeedtech.com/ckfinder/userfiles/files/33036985498.pdfIn PDF document text
    • https://copacndg.com/images/uploads/files/motesemokifot.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/161409be11a729---10693658308.pdfIn PDF document text
    • http://chinajnbt.com/images/upload/File/luditikatoriwepiwapit.pdfIn PDF document text
    • https://orrizon.ru/images/file/saniz.pdfIn PDF document text
    • https://brincandoeaprendendo.com/fotosempresa/files/23289537644.pdfIn PDF document text
    • http://www.parkwaytransplant.com/media_upload/upload/files/10139863448.pdfIn PDF document text
    • http://school15-tyumen.ru/f/mukodesamirugew.pdfIn PDF document text
    • https://mashura.co/userfiles/files/jisimipebotunan.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16143c56f64a52---bilarataxawegifil.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614170a947495---vobopigiseripev.pdfIn PDF document text
    • http://petraifevronii.ru/ckfinder/userfiles/files/laxodadejiwuz.pdfIn PDF document text
    • https://nsstore.mx/ckeditor/ckfinder/archivossubidos/files/kexezebepum.pdfIn PDF document text
    • http://zeguvietnam.com/uploads/ckfinder/files/80714457429.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_off0000b73c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB73C 15796 bytes
SHA-256: 6a900c416dc7b2fbb3c21e011cb4c8bf971ccec0096156ea897e9ff51a8484ac
font_01_sfnt_off0000df87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF87 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f79e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF79E 10840 bytes
SHA-256: 0f14d426c541f61da2b4738368b3abbfcc7bdc9c0d5f405c1077d19fe97a43b0