Malicious PDF — malware analysis report

Static analysis result for SHA-256 dd138eaef1753b1b…

MALICIOUS

PDF

80.7 KB Created: 2021-09-19 19:17:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 9287e2c3f2b24de242fb7be62a7179c6 SHA-1: 7643944a026509bb40f1bb3070cf12545d2e00d1 SHA-256: dd138eaef1753b1b9905914da17b9cf01f045b9799ed583d468ad8166d3d8654
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 WordPress sites or disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://catamma.ru/uplcv?utm_term=best+android+chat+rooms PDF link annotation
    • http://ewhamd.net/upFiles/ckeditor/files/96034166472.pdfIn PDF document text
    • http://bassbasement.org/userfiles/file/96897084933.pdfIn PDF document text
    • http://mylodge-naoshima.com/images/blog/file/sakaxed.pdfIn PDF document text
    • http://bonezi.morefriendship.com/upload/files/luwopofivasizowu.pdfIn PDF document text
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/65a089ea90e6181d0bb646823753dc55/84801354019.pdfIn PDF document text
    • http://fruitvita.com/files/files/luwesov.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b579628bd2---75607417096.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613a71d5a2bac---43425328531.pdfIn PDF document text
    • http://www.pantonerestauri.com/ckfinder/userfiles/files/lomofisefofopum.pdfIn PDF document text
    • https://terracell.pt/images/file/firerikurixodajoreb.pdfIn PDF document text
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/161362c9a78890---lizupumojebovaledoxif.pdfIn PDF document text
    • http://dade666.com/userfiles/202109file/2021090414513170554.pdfIn PDF document text
    • https://m-astar.com/UserFiles/files/puletukoluwinolelujaf.pdfIn PDF document text
    • http://studiozammuner.eu/userfiles/files/590434910.pdfIn PDF document text
    • http://jiin-torng.com/uploadfiles/20210906160902.pdfIn PDF document text
    • http://draftingfloorplan.com/ckfinder/userfiles/files/83235738757.pdfIn PDF document text
    • http://kfoodntea.com/dataroom/file/64154187255.pdfIn PDF document text
    • http://seibyou-koujien.com/files/files/5370529773.pdfIn PDF document text
    • https://fnb-concepts.com/images/uploads/files/lademil.pdfIn PDF document text
    • http://kepco-group.com/uploaded_files/userfiles/files/nowonituxopiwa.pdfIn PDF document text
    • http://lachina.cn/upload/file/53529420750.pdfIn PDF document text
    • https://escaletravel.com/userfiles/files/gomobonune.pdfIn PDF document text
    • http://ottomaniantextile.com/userfiles/file/topesaziluto.pdfIn PDF document text
    • http://galettedesrois.eu/userfiles/file/fopabosamizaxoratovazitek.pdfIn PDF document text
    • https://cualuoihoanmy.com/uploads/userfiles/file/muzib.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_off0000d5f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5F7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ee09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE09 18244 bytes
SHA-256: 605d0a4b505de45d7977334cb5f48141b1a8fc652787b3431909f307869b3066
font_02_sfnt_off00011d02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D02 10640 bytes
SHA-256: ea539e429d2b2e85fb27cdeb46e1f9bb3b11d1e592d09b2f6179601726b4dad5