Malicious PDF — malware analysis report

Static analysis result for SHA-256 3754df9d0748a899…

MALICIOUS

PDF

69.7 KB Created: 2021-09-16 03:05:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 6a10918cba77297b64b6111c6f7bba28 SHA-1: 151f72fc245f29648d88ff8cfbcc2bf7355fe5ad SHA-256: 3754df9d0748a899aa4ab0a3ce741b2f1e4d511b6e0e04219de31e3204d0580d
96 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to disposable domains or compromised CMS upload directories, suggesting a link farm or SEO spamming operation. The ML classifier strongly indicated maliciousness, and the presence of compromised upload links points to a potential distribution vector for further malware. While no scripts were extracted, the structure and URL analysis strongly suggest a malicious intent to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 5

  • 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 http://fitviewer.info/files/file/titisagapir.pdf In PDF document text
    • https://peterdegendt.be/file/65530577211.pdfIn PDF document text
    • https://taiwancy.com/app/webroot/userfiles/files/viteb.pdfIn PDF document text
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/a2b64689e3c71be5dd84a211aa235bfd/napaxibonovajusa.pdfIn PDF document text
    • https://dondepodemosir.com/userfiles/file/rononawe.pdfIn PDF document text
    • https://dukeofmarshall.com/ckfinder/userfiles/files/fazofilo.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16140aecbe31b9---50344549914.pdfIn PDF document text
    • http://vizit-k.net/uploads/editor/files/37835362091.pdfIn PDF document text
    • http://fbrasil.com/userfiles/file///51864852048.pdfIn PDF document text
    • http://unityproductions.com/upload/files/posadaxadinosituluki.pdfIn PDF document text
    • http://prvugkh.ru/uploads/files/kemaluduselapulap.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/161422a813d41f---xopuvasemuma.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fe9854e281---jajonosuluduxolobexokiw.pdfIn PDF document text
    • http://khaskhaan.mn/uploads/userfiles/files/fabemobajurojolobo.pdfIn PDF document text
    • http://kamakuralosgatos.com/uploads/files/dujakibexomulinasekonijaw.pdfIn PDF document text
    • http://www.cenlaenvironmental.com/siteuploads/editorimg/file/78358928283.pdfIn PDF document text
    • http://davidhammerstein.org/ckfinder/userfiles/files/laduxivod.pdfIn PDF document text
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161406378bb0c8---27469898440.pdfIn PDF document text
    • https://thieumaunao.vn/workspace/develop/uploads/ck_upload/files/kuwutaputaxumav.pdfIn PDF document text
    • https://nutstudio.it/userfiles/file/61104653437.pdfIn PDF document text
    • https://oolong-dining-co.com/webroot/editor-uploads/files/98981844297.pdfIn PDF document text
    • https://blv.by/upload/editor/files/fuforigitewanizinin.pdfIn PDF document text
    • https://matfplayer.com/calisma2/files/uploads/gibinu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=casino+bonus+codes+australiaPDF 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_off0000b30a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB30A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB1C 14920 bytes
SHA-256: 903f6beb06666c04859a1b0b9f2a67abe785a4c053826a422355100a0a26db9b
font_02_sfnt_off0000f06d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF06D 10636 bytes
SHA-256: 27f66eb1c5a6338b63a3286bcb9ed89b3140a5bcd8a6d2ffc6f980defbfa0864