Malicious PDF — malware analysis report

Static analysis result for SHA-256 0e5b8b56b27170e2…

MALICIOUS

PDF

81.6 KB Created: 2021-09-17 04:10:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 79c69cbc18760aff0c777175d3809961 SHA-1: 871940518a47f3891dc438fd53e4e0cf78361ad0 SHA-256: 0e5b8b56b27170e2f1543834852d28c14013739fa340bdd64ac985a21ed9eb5d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

This PDF file contains embedded JavaScript and multiple external URIs, many of which point to compromised WordPress sites acting as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely facilitates the redirection or execution of further malicious content, while the link farm structure suggests an attempt to obscure the ultimate destination and evade detection.

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
  • 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 https://krisoc.ru/uplcv?utm_term=mhtml+reader+for+android PDF link annotation
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613a9ec87b922---norix.pdfIn PDF document text
    • http://ty-universe.com/image/files/20210910_095042.pdfIn PDF document text
    • http://floridadressyourhome.com/uploaded_files/userfiles/files/vofoxabuguzosedixopavan.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/161415b2be3997---kixog.pdfIn PDF document text
    • https://pellevah.com/upload/files/6085850143.pdfIn PDF document text
    • http://kes.org/upload/editor/files/21334608993.pdfIn PDF document text
    • http://crystalnymph.by/wp-content/plugins/super-forms/uploads/php/files/ef18bb51047d3520bcb3b9376860d754/jozotobisamelupitin.pdfIn PDF document text
    • https://papiratisk.cz/soubory/jokiza.pdfIn PDF document text
    • http://masan315.net/board/imagefile/file/jezadafaxananedekidinod.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/161382e5309112---64564466690.pdfIn PDF document text
    • http://nousgarage.com/userfiles/file/fawetuziji.pdfIn PDF document text
    • http://np-laser.com/upload_fck/file/2021-9-16/20210916141931697353.pdfIn PDF document text
    • http://hutnia.pl/userfiles/file/97090068039.pdfIn PDF document text
    • http://skontrolsengineering.com/file_media/file_image/file/piwutewuninupafutukefil.pdfIn PDF document text
    • http://harasim.cz/uploaded/files/54688630015.pdfIn PDF document text
    • https://caraudioshop.ro/mm/file/35474343870.pdfIn PDF document text
    • https://skinrepublic.vn/webroot/img/files/pusofanegelu.pdfIn PDF document text
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/9c814c970a3929fcf39c80bc6be5db10/nitin.pdfIn PDF document text
    • https://westhygiene.hu/editor_up/39477900.pdfIn PDF document text
    • http://xn--9w3b270a7kf.kr/ckfinder/userfiles/files/mewuzemetaxivodaxedeb.pdfIn PDF document text
    • https://ciiinnovationsummit.com/ci/userfiles/files/14431864493.pdfIn PDF document text
    • http://munnartourism.com/uploads/file/73698195480.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/161363ae00ac8f---54975057852.pdfIn PDF document text
    • https://minervatech.work/js/ckfinder/userfiles/files/vokibu.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_off0000d526.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD526 19096 bytes
SHA-256: ae65cde0e2d7190255e70a9e6b680d09a6806b527234164c71140790bda5ef6e
font_01_sfnt_off0001075d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1075D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011f74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F74 10444 bytes
SHA-256: 8e60994477d8ccbee9593deccb00fe9f0ff904a580f39a758e8d79281cea8c86