Malicious PDF — malware analysis report

Static analysis result for SHA-256 091328e489e5aaa1…

MALICIOUS

PDF

80.2 KB Created: 2021-09-19 08:57:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 4eb47ed59e019d4bb570ac6abfa5768d SHA-1: c1c95b4141b7730d28900a1e78b72b410d3dbf8d SHA-256: 091328e489e5aaa1edd67dc95cea8067b8bcb6f15434b8ef633fb6c35702a675
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document containing embedded JavaScript and multiple external links. One high-severity heuristic indicates a PDF link to an algorithmically-generated URL, and another flags the PDF as a link farm on disposable hosting. ClamAV also detected this file as Pdf.Phishing.Trojan. The embedded JavaScript and the suspicious URLs suggest an attempt to redirect the user to a malicious site, likely for phishing or to download a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://studiomedicoveterinariobellucci.eu/userfiles/files/saxipidesigudigozuxod.pdf In PDF document text
    • http://citranco.com/users/files/medanubexipalo.pdfIn PDF document text
    • http://yejiya.com/userfiles/file/kirigasepikatoribinu.pdfIn PDF document text
    • https://hopclickhospitality.com/scgtest/team-explore/uploads/files/3592417994.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/1612fbd5b8b87b---zijibije.pdfIn PDF document text
    • http://techbis.pl/files/file/33205418182.pdfIn PDF document text
    • http://e-restauracion.com/app/webroot/files/uploads/files/navobagilate.pdfIn PDF document text
    • http://topliving.sk/userfiles/file/20334229501.pdfIn PDF document text
    • http://guanzhuli.com/userfiles/file/siguvovigexufurutuxululeb.pdfIn PDF document text
    • http://saipanbooking.com/FileData/ckfinder/files/20210911_5D12E86CF8D4B8EA.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/161453831d33eb---5767392538.pdfIn PDF document text
    • http://hoteldanang.com/uploads/images/files/16727776.pdfIn PDF document text
    • https://kenkochaya.com/user_data/ckfinder/files/tugutebedisugos.pdfIn PDF document text
    • http://volvo-cars.jp/js/upload/files/jejemasuxebukuvaxujopan.pdfIn PDF document text
    • http://jmlukanich.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/pugemenivun.pdfIn PDF document text
    • http://sedaciesupravy.sk/media/file/67801436092.pdfIn PDF document text
    • http://giteduguedesboires.com/userfiles/file/57137912399.pdfIn PDF document text
    • http://phone-server.com/userfiles/file/24966822558.pdfIn PDF document text
    • http://simsoncantho.com/userfiles/file/zizemurajasawiwibujulifid.pdfIn PDF document text
    • http://www.sintsprev-ms.org.br/ckfinder/userfiles/files/tumekotu.pdfIn PDF document text
    • https://mrpressconsulting.com/UserFiles/file/waxujebiwekumota.pdfIn PDF document text
    • http://learnersdigest.org/userfiles/file/22077488578.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=how+to+transfer+pictures+from+my+phone+to+my+pcPDF 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_off0000d6cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6CF 10988 bytes
SHA-256: 9cb29001390fec5ce3b9f34b83cbc85e54b2b026f0db12a63d88ac668b2d4a0a
font_01_sfnt_off0000f031.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF031 16300 bytes
SHA-256: 7a6c04571aff67ca0c93d1a91c19a22878143e3eb343c5755581e7d143603498
font_02_sfnt_off00011a56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A56 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1