Malicious PDF — malware analysis report

Static analysis result for SHA-256 f7929d51c0ac7f0a…

MALICIOUS

PDF

80.9 KB Created: 2021-09-19 11:13:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1b72762b3ce5c4bba1a6c6e2158be83f SHA-1: f9c8cb63850af1e188f0f0745d5b7274c77ac286 SHA-256: f7929d51c0ac7f0ab94923cf687596214a4dc1d76b3f604e0e9622a2e64683c9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to disposable hosting or compromised WordPress sites, indicating a link farm for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and link farm heuristics are indicative of a malicious document, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://irlanc.ru/uplcv?utm_term=windows+7+home+premium+net+framework PDF link annotation
    • https://onutglen.com/caningest/images/file/dazakakudefozanonom.pdfIn PDF document text
    • http://61kidsclub.com/userfiles/file/kezuzokunukeg.pdfIn PDF document text
    • http://dijladentalcenter-qa.com/userfiles/file/jagimewari.pdfIn PDF document text
    • http://azizavacanze.com/userfiles/files/89746917955.pdfIn PDF document text
    • http://hengtongrongshang.com/jingkelun/userfiles/files/20210914051707.pdfIn PDF document text
    • http://lauraestetica.com/userfiles/files/wefamonoreduku.pdfIn PDF document text
    • https://sapsda.org/SapmaUserfiles/file/zuseja.pdfIn PDF document text
    • http://thuocnam.xyz/images/files/83712688584.pdfIn PDF document text
    • http://coaching-scolaire.net/userfiles/file/35596623835.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/jt5qdnb1e6e7rqqtta7q57sbhr/18125160062.pdfIn PDF document text
    • http://xinyuemu.net/assets/202109/files/20210917055551846217.pdfIn PDF document text
    • http://hzxgdz.com/images/upload/File/97469757109.pdfIn PDF document text
    • http://gonvvama.net/filespath/files/20210908233016.pdfIn PDF document text
    • https://yourownadviser.com/ckfinder/userfiles/files/73020984963.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613aeb4857933---dowilakonefurorod.pdfIn PDF document text
    • http://www.louisefarmersmith.com/admin/ckeditor/ckfinder/userfiles/files/dojegakabenipawoziki.pdfIn PDF document text
    • http://lideparts.com/userfiles/file/1631717799.pdfIn PDF document text
    • http://italy-ex.com/images/blog/file/rexudovu.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613f6f311984b---57511296939.pdfIn PDF document text
    • https://siangyun.com/upfiles/editor/files/95980274656.pdfIn PDF document text
    • https://emotionalgift.youngzonejewelry.com/ckfinder/userfiles/files/20291900385.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_off0000d4a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4A5 18260 bytes
SHA-256: 4c619edec3fa8693c0f75fe8ad77061eec4df7fafdea39d434dac019254bd5e1
font_01_sfnt_off00010427.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10427 11040 bytes
SHA-256: 279442b55128f67ee56cdbeaa8f58ebf033f773b4759d1707121547a00cbd14e
font_02_sfnt_off00011dbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DBD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1