Malicious PDF — malware analysis report

Static analysis result for SHA-256 a40291b8bab3c447…

MALICIOUS

PDF

87.0 KB Created: 2021-09-18 14:19:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 788f83c7d6fc20d3ceb6d8ddea417a00 SHA-1: ea757df138750c4a70b2d02367490d1a0c790572 SHA-256: a40291b8bab3c4472324abdc61cdc4f0ba439f731ffcd0141b9fc5800137ba37
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs, many of which point to potentially compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URI patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://pixomot.ru/uplcv?utm_term=game+korea+offline
    • http://master-vin.ru/files/file/57438886006.pdf
    • http://kiajihlava.cz/UserFiles/File/tadaputotiraxodujasedaluv.pdf
    • https://alkirbilaw.com/userfiles/files/sejebu.pdf
    • https://servauto.fr/img/user/file/veveruxugerika.pdf
    • http://paglialonga.it/userfiles/files/sujuv.pdf
    • https://attackworkoutprogram.com/app/webroot/files/ckfinder/userfiles/files/navalu.pdf
    • http://ndt-tl.ru/upload/file/mufejowixewum.pdf
    • https://amatnieks.com/pictures/image/novabidifejibotagiduno.pdf
    • http://hoangduy.vn/vn/files/vanemizaxuk.pdf
    • https://senesi-sklad.cz/userfiles/file/sejobopizoxoliru.pdf
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/489954708a24392d2c957ef681bda46b/vuvovaxuvagi.pdf
    • http://185.33.116.142/~bbyacht01/upload/files/28573860182.pdf
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/paba84q680vdnu9pcj8ji787hq/99747000856.pdf
    • http://swhos.com/upload/files/mabitadiloranapofidajob.pdf
    • https://havilahbuilders.com/userfiles/file/38452181365.pdf
    • http://jca-t.com/fck_image/file/dapasalifixobesuxu.pdf
    • http://hsaltsj.com/uploads/files/mikawexafizobumi.pdf
    • http://asdgolfclubtoscana.com/writable/public/userfiles/file/47558239518.pdf
    • https://4cmedica.com/ficheiros_upload/file/39176176431.pdf
    • https://www.truck-transport.com/ckfinder/userfiles/files/tepawifufasutotuvepuzoba.pdf
    • https://chungcungoaigiao.vnpec.xyz/uploads/files/kelagumulel.pdf
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/8f1cb7588462f6abf60f9f397d7dff2c/65244554066.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614074a94d0b5---merijufonujof.pdf
    • https://osakaav.com/userfiles/files/fefikofeta.pdf
    • https://producedepot.us/userfiles/files/40871295886.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f2e2.bin
19e48bde3fb4b049662134f6f17926e4358bdecae808f0009d57a568a09b8313
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2E2 17168 bytes
font_01_sfnt_off00011f85.bin
497456b2fc4d89fa071c5a5887a12e9290860bc919bd39ed74ac39e0e0f22332
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F85 10240 bytes
font_02_sfnt_off0001366d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1366D 16792 bytes