Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8427f484319f2ce…

MALICIOUS

PDF

81.9 KB Created: 2021-09-18 22:29:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 38484a5a7fcba3207c7c0dc550804e1d SHA-1: 42232486d0bb152205a3663bb2d63301d2fd2499 SHA-256: c8427f484319f2ce3cdb3bc26115cee24fc61f3681d3ed3e22d929f80ae12171
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress uploads and disposable hosting, suggesting a link farm designed to distribute malware. The presence of a ClamAV detection for 'Pdf.Phishing.Trojan' and ML classifier flagging further supports its malicious nature. The document body is heavily obfuscated and unreadable, but the heuristics indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133962e08c27---rifozazewuwelij.pdf In PDF document text
    • http://skkl.cn/filespath/files/20210902030151.pdfIn PDF document text
    • http://locke-3c.tw/uploads/files/202109172302147179.pdfIn PDF document text
    • https://maxflowfans.com/userfiles/file/28785585836.pdfIn PDF document text
    • http://dc-a0dcf319a153.breakthroughsport.com/userfiles/files/52755462424.pdfIn PDF document text
    • http://shinex-auto.com/userfiles/file/jobofufesizumekenup.pdfIn PDF document text
    • https://sapporomn.com/userfiles/files/zogapatazoxuzib.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613726e416557---99918028989.pdfIn PDF document text
    • http://gongotour.com/FileData/ckfinder/files/20210910_7FBD2E7D01993F1A.pdfIn PDF document text
    • http://tcsklife.com/filespath/files/20210910161055.pdfIn PDF document text
    • https://haciendaloscipreses.cl/upload/file/63667918613.pdfIn PDF document text
    • http://luckdidea.com/ckfinder/images_store/files/95421270614.pdfIn PDF document text
    • http://montaze.org/democms/userfiles/file/kuzufajunasozoxabesog.pdfIn PDF document text
    • http://ansatrans.ru/admin/ckfinder/userfiles/files/mesawegodij.pdfIn PDF document text
    • https://nnt52.ru/userfiles/file/nobeludamanepojed.pdfIn PDF document text
    • http://designerhouse.ru/upload/files/29544280007.pdfIn PDF document text
    • http://ketoanantamhcm.com/uploads/files/23718804322.pdfIn PDF document text
    • http://cosmikkino.ru/sadm_files/20741038947.pdfIn PDF document text
    • http://lapenya.cat/imgjovesnaves/file/teniliziduvufolekumuwuve.pdfIn PDF document text
    • http://bakoca.hu/files/file/durafafo.pdfIn PDF document text
    • http://ailizia.com/userfiles/47399323876.pdfIn PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/ac70fc04c70c2b7c4a995cf1f52f8ba4/namowireximosafakiwimofi.pdfIn PDF document text
    • http://palazzodiaz.com/userfiles/files/nazapowi.pdfIn PDF document text
    • https://nedimgame.com/calisma2/files/uploads/sofenaxelik.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=kali+linux+nethunter+apk+download+for+androidPDF 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_off0000d7c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7C0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000efd2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFD2 18100 bytes
SHA-256: ffddbc92ac682915fce48d0c4ef8360b681104da94e38bba6a8fa58dc43c85ca
font_02_sfnt_off00011f00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F00 10796 bytes
SHA-256: 93ea2d807ba471263b5a7ff398ee0baa1256790f3388d2dd75f587dbeb1ddd84