Malicious PDF — malware analysis report

Static analysis result for SHA-256 907695d76607e40f…

MALICIOUS

PDF

75.7 KB Created: 2021-09-17 01:11:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: cdcc0b2bdaaf3306f90d9053cf04e5c1 SHA-1: 528d09f55df37a7cfe64b85c28aad5e0e5f57cc5 SHA-256: 907695d76607e40fe2798c482a23801f5c6bee3d6180fea3b241ed86e5d03a1b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS uploads, indicative of a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the PDF structure itself is used to host and present these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://marugame.hk/editor_upload/file/18020835418.pdf In PDF document text
    • http://terrietanaka.com/library/files/45819409035.pdfIn PDF document text
    • https://dycmc.com/DATA/upload/files/202109050119088179.pdfIn PDF document text
    • https://jordanadams.com/ckfinder/userfiles/files/moritatepedolobe.pdfIn PDF document text
    • http://evrokomplekt.ru/userfiles/file/wafivulesomolizowamipuda.pdfIn PDF document text
    • http://taiwan-tsai.com/upload/files/4549197192.pdfIn PDF document text
    • https://arrayamed.com/userfiles/file/redaje.pdfIn PDF document text
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ebc10b39fa---belejijoxidemaka.pdfIn PDF document text
    • http://vucert.vn/uploads/files/fakujibotigixipunisitiri.pdfIn PDF document text
    • http://ez-surveying.com/htdocs/cljr/data/files/zuxiganokatulogalade.pdfIn PDF document text
    • https://consultingexpert.eu/fckeditor/userfiles/file/fodoboxurudowi.pdfIn PDF document text
    • https://functionalmovement.gr/wp-content/plugins/super-forms/uploads/php/files/356742d374165e444a22ebbb3b581d76/90687029482.pdfIn PDF document text
    • http://praguynakorn.com/praguynakorn/picture/datapro/files/98428740608.pdfIn PDF document text
    • http://zensushialiso.com/uploads/files/zavolajuviruvuga.pdfIn PDF document text
    • http://kiapelhrimov.cz/UserFiles/File/62111055321.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b13434ce74---nugezitesifewir.pdfIn PDF document text
    • http://gernano.eu/gfx/userfiles/files/fezisulabalazozoleb.pdfIn PDF document text
    • https://himarco.ir/basefile/himarcoir/files/rugojakupoka.pdfIn PDF document text
    • http://www.culturehousesun.org/photos/file/91169067605.pdfIn PDF document text
    • https://www.ksmt.edu.np/assets/ckfinder/userfiles/files/dodoraxazusukopumigosowo.pdfIn PDF document text
    • http://vongtaygiay.net/media/ftp/file/8245601599.pdfIn PDF document text
    • http://xn--9p4b29dncp2cc6y.net/upload/fckeditor/file/44422916668.pdfIn PDF document text
    • http://snp-ent.com/files/fckeditor/file/1354295728613355ac7cce6.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=pokemon+go+auto+walk+appPDF 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_off0000c1eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1EB 17968 bytes
SHA-256: 71e803b64b7cdea27c4b39ea1d671b9b64ba262de9561455603e94099ba2771f
font_01_sfnt_off0000f0f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0F3 10512 bytes
SHA-256: 192985f87cb41c051b1dc09ba703a2b94d0b4705850154434450f758d3f4995c
font_02_sfnt_off000108fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108FE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1