Malicious PDF — malware analysis report

Static analysis result for SHA-256 34c91b90ad5938b3…

MALICIOUS

PDF

97.3 KB Created: 2021-09-15 21:10:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 406e2b13cc597923c18e1992535b0393 SHA-1: 8229a2fac9292ba5e806a92eaf7ad43f45e980f6 SHA-256: 34c91b90ad5938b3113c6b76316ccc269834ae9b14ef929a78b7c23db6235a4b
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to disposable hosting or compromised CMS upload directories, indicative of a link farm used for malicious purposes. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://renteci.com/imagens/file/78701468379.pdf In PDF document text
    • http://stapper.de/sites/default/files/userfilesfile/9673544873.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/73282346968.pdfIn PDF document text
    • http://soeurs-scjboran.fr/soeurs/upload/files/kedugagekozozosukofaloxel.pdfIn PDF document text
    • http://iviltra.lt/images/files/61088958303.pdfIn PDF document text
    • http://jr.ac.th/ckfinder/userfiles/files/rivaranaxinufusukukoju.pdfIn PDF document text
    • http://mayjack.com/upload/files/93172371431.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/77fdbc8139d06a9518531ac8159cb6e8/mopovofadofatamenim.pdfIn PDF document text
    • https://www.huaikrachaohospital.go.th/assets/global/lib/ckfinder/userfiles/files/lizanef.pdfIn PDF document text
    • https://prana.video/wp-content/plugins/super-forms/uploads/php/files/0dhhld27ab72q7olfufnvknugu/fowumarelibumat.pdfIn PDF document text
    • http://chiaranannini.com/userfiles/files/86904881079.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/zakifezufezenakozesovij.pdfIn PDF document text
    • https://www.tahitotfaluovodak.hu/ckfinder/userfiles/files/54351016486.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/kd4olehemf06hvh7f0tijaqgl9/zovozexegujapirakol.pdfIn PDF document text
    • https://bhiringisamsankalimandir.org/userfiles/file/xagive.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613706b722f5c---zefivadejekazogixaguvuzo.pdfIn PDF document text
    • http://td-mg.ru/uploads/files/dukeduladutewamimobodi.pdfIn PDF document text
    • https://tonere.shop/app/webroot/files/userfiles/files/34885675321.pdfIn PDF document text
    • https://hitourkorea.com/FileData/ckfinder/files/20210914_1B810013C77B7452.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/161414d12dd780---terokuv.pdfIn PDF document text
    • http://demenagements-remond.fr/userfiles/file/20210902120846.pdfIn PDF document text
    • https://degardo.hollandpazsit.hu/ckfinder/userfiles/files/1136785413.pdfIn PDF document text
    • http://upservice.expert/admin/ckfinder/userfiles/files/napexaterila.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=poco+x3+nfc+gps+problemPDF 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_off0001180d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1180D 17912 bytes
SHA-256: 244b8ae9e9d7919544d228917872b308a08907cf1f1b8b7a22e688b43bca31c3
font_01_sfnt_off000146c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x146C5 10884 bytes
SHA-256: 49a6a4bf8e512994b03c2ad1089289beb551d1fef7190a7df4c1ea85fa777fb4
font_02_sfnt_off00015fcd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15FCD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1