Malicious PDF — malware analysis report

Static analysis result for SHA-256 350c104d58a18409…

MALICIOUS

PDF

80.1 KB Created: 2021-08-17 14:13:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 0f4cfea08f22771b91196efea919d67b SHA-1: 1c2fdd0175ecc65ae8a2f2107cff55f60f1b4fbb SHA-256: 350c104d58a18409d0addc98fa8b2ad6bcff4f86612513e24d4c47ad8f504e99
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains embedded JavaScript, which is often used to execute malicious actions or redirect users. The presence of numerous external URIs, including links to compromised CMS uploads and disposable hosting, suggests a link farm designed to obscure the ultimate destination and potentially distribute phishing content or malware. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a non-clustered link farm on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://huntland.hu/upload/file/tuzodagujiro.pdf In PDF document text
    • http://cephedanismani.com/images/pages/file/jamikasufavimek.pdfIn PDF document text
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/kfebgqj9vb71hbmn6vgcrfe254/xosuru.pdfIn PDF document text
    • http://poney-club-romilly-aigre28.fr/userfiles/file/xotuteki.pdfIn PDF document text
    • https://777mto.com/contents//files/65882704296.pdfIn PDF document text
    • http://upasamed.org/Content/uploads/files/86886538405.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608dd70a12c4b---xivowu.pdfIn PDF document text
    • http://praguetransfer.com/files/file/43144151502.pdfIn PDF document text
    • http://thegioichuyendong.info/app/webroot/upload/files/rezujowepevejineru.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/41324f31a7f2e4162c1d98b064406972/4193956279.pdfIn PDF document text
    • https://zerling.eu/nico/images/files/nuzamafikikofowafubaw.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/iiuj5qruc2gr9ujpaeiolb31qh/60657920868.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/qh7st1kt6rfom2s53og461luvj/44699323226.pdfIn PDF document text
    • https://acronimocostanzo.com/userfiles/file/zadawagilijebisodowon.pdfIn PDF document text
    • http://carshopm.com/js/upload/files/bokuz.pdfIn PDF document text
    • http://pogotowienaukowe.com/Upload/file/3104092129.pdfIn PDF document text
    • http://e-pisanie-prac.pl/famprojekt_z_serwera/images/file/9964682421.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/160986dc363dd0---vusejopifumid.pdfIn PDF document text
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/cc1985f11a1e1b870b4366184fab8dc9/kukemexetepubaputumonuba.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/88d9526de0c79e7a18628e83a0cfa73b/74530313648.pdfIn PDF document text
    • https://suma.ca/upload/editor/file/tibulisej.pdfIn PDF document text
    • http://toyotarent.hk/FileData/ckfinder/files/20210702_7540C97658ADF249.pdfIn PDF document text
    • http://thebrownsfamilyreunion2008.com/clients/81208/File/kunusop.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=how+to+get+free+kr+in+krunker+hack+2021PDF 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_off0000d3fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC11 10964 bytes
SHA-256: 801da5ee08e49aad04b4d6b1703bef1d187c1bc04c46be57cda994918702b155
font_02_sfnt_off00010594.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10594 16880 bytes
SHA-256: 8f359be377f268718537b634336ed9070a11ebaad36e04eaf4b1b6fa83fd31dd