Malicious PDF — malware analysis report

Static analysis result for SHA-256 7da4686cc80d58e1…

MALICIOUS

PDF

77.6 KB Created: 2021-09-16 08:19:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 92d98573a6fe4d588107acb4b8b7147d SHA-1: 8b12b481458104d9408423fdb588be09dd01efb8 SHA-256: 7da4686cc80d58e160d12e54721e3726c0e7e8c752a4765bc1052fe9371d24f3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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://synerhu.ru/uplcv?utm_term=eating+in+the+light+of+the+moon+free+pdf PDF link annotation
    • http://yourhealthyanswer.com/ckfinder/userfiles/files/45509683362.pdfIn PDF document text
    • https://theipbuzz.com/images/file/ruzajibijawipesevo.pdfIn PDF document text
    • http://prosquash.by/data/86079540695.pdfIn PDF document text
    • https://alarouba.com/ckfinder/userfiles/files/zapavokawina.pdfIn PDF document text
    • https://nbc.com.vn/ckfinder/userfiles/files/4826187300.pdfIn PDF document text
    • https://h1t-urlaurora1-turbo.com/contents/files/60023247071.pdfIn PDF document text
    • https://kstraders.com/userfiles/file/20805583705.pdfIn PDF document text
    • http://stlukesfp.org/ckfinder/userfiles/files/80356583317.pdfIn PDF document text
    • https://thietbixanh.net/uploads/files/99541236276.pdfIn PDF document text
    • http://oio.cn/uploadfiles/files/44560686860.pdfIn PDF document text
    • http://koopmankennedyfeller.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/18771338044.pdfIn PDF document text
    • https://chameleoncoupons.com/adgprocessing/uploads/files/nivuwitu.pdfIn PDF document text
    • https://pmfegypt.com/userfiles/files/wadodavifukipizagubewobu.pdfIn PDF document text
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/fd2ccea8e58ce29ef3a91ba9d347ce5d/34406102558.pdfIn PDF document text
    • http://escritacontabilidade.net/fotos/news/file/9586331547.pdfIn PDF document text
    • https://laetitiabernard.fr/images/file/73618597478.pdfIn PDF document text
    • http://maturitni-ples.eu/UserFiles/File/98180797739.pdfIn PDF document text
    • http://yjsyrj.com/userfiles/file/7358727820.pdfIn PDF document text
    • https://mariapolis.net/ckfinder/userfiles/files/33990411314.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/161329ff5f3c60---nesapodaratobosir.pdfIn PDF document text
    • http://3colorjazz.com/fckeditor/userfiles/image/81926849995.pdfIn PDF document text
    • http://formel1vermietung.de/userfiles/file/75980145305.pdfIn PDF document text
    • http://csim.jp/ckeditor/uploads/files/xopejar.pdfIn PDF document text
    • http://tea-ra.com/user_data/upload/save_image/files/3874940941.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/p6eimqpb88l72edg6cdjt4v7vo/98570640280.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_off0000c9f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9F4 17920 bytes
SHA-256: a28f58e8b3279780721f449ad8fb7c830f43f02e622e0fb898298fcd2079c8d9
font_01_sfnt_off0000f82f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF82F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011046.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11046 10760 bytes
SHA-256: 90815c2dab41fb01630383c97211f9c365fa944c5f0b70e457148fba45967259