Malicious PDF — malware analysis report

Static analysis result for SHA-256 a67bb67ff36d59e5…

MALICIOUS

PDF

69.1 KB Created: 2021-09-28 18:37:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: d018d8d09fa955f4fdcf14754c6c236e SHA-1: 2e2453a8c12b4b370d6e1afb0802f2b9b0af6a08 SHA-256: a67bb67ff36d59e5351dc7a4eba4715fddb897bebc270df528218121b4046795
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of links, many hosted on disposable domains or compromised CMS upload storage. These links appear to be part of a link farm designed to redirect users to download files, as suggested by the URL parameters like 'camscanner+premium+version+apk'. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for distributing malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://arkystudio.eu/userfiles/files/volafanu.pdf In PDF document text
    • https://optical-axis.com/uploads/files/202109181242293260.pdfIn PDF document text
    • http://eggtesting.com/admin/uploads/file/kotazajigitinefovanujur.pdfIn PDF document text
    • https://havilahbuilders.com/userfiles/file/27589687255.pdfIn PDF document text
    • http://pelejas.com/IMAGENS/CKFINDER/files/46426408896.pdfIn PDF document text
    • http://titibbs.xyz/js/ckfinder/userfiles/files/23546696244.pdfIn PDF document text
    • https://pharma-tools.pl/galeria/file/52792847144.pdfIn PDF document text
    • http://zhizhencn.com/filespath/files/20210909020230.pdfIn PDF document text
    • https://ladymamashop.com/uploads/files/202109041444151702.pdfIn PDF document text
    • https://medsplus.us/admin/images/file/fabelamafosuwa.pdfIn PDF document text
    • https://confidence-ist.mktechsol.com/ckfinder/userfiles/files/digowusadimifofotop.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/161413cc8b0827---74945008335.pdfIn PDF document text
    • https://xn--i1aam8cb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/76432ce09601007b809c57c20cc74c54/lanonar.pdfIn PDF document text
    • http://alajwakh.com/uploaded_files/userfiles/files/tiwexibogikevubomopip.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148da99514d9---suxiref.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/16137cfd64ec93---kideju.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1614fafaac7871---52273124596.pdfIn PDF document text
    • http://yangs-ns.com/ckfinder/userfiles/files/20210904015734.pdfIn PDF document text
    • http://cmuniontravel.com/userfiles/file/rejafaxakenasowubur.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=camscanner+premium+version+apkPDF 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_off0000ac53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAC53 16608 bytes
SHA-256: d1da5deb6bb2a6dc8598346e87a8bf13cee7670d5cf817d133f20b80b4dc13ca
font_01_sfnt_off0000d671.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD671 10680 bytes
SHA-256: 7bc45891799d8a73123a68ba50c3aa73418a34b1aeab5c63e46e6abb226b6acc
font_02_sfnt_off0000eef4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1