Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1b25aa7dcd61415…

MALICIOUS

PDF

75.0 KB Created: 2021-06-27 02:49:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 0b69c4f371fe38e3978721ecddb5f23f SHA-1: 5592bda1d2ef32235254a1e62e6864b4ceb971ae SHA-256: a1b25aa7dcd61415e249a923a5bceb2b5a678582ced7ea615d4c9eb701e98752
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, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links. No scripts were extracted, but the structure and URL patterns are indicative of a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e7e8c731c6---72031080538.pdf In PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/b635f87cb7fe51696c6838e4f5f350d7/wonovosejalu.pdfIn PDF document text
    • https://www.icslights.com/wp-content/plugins/super-forms/uploads/php/files/a9acbe8b965d9269a1f1a9a304ded840/68242561491.pdfIn PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9b62727512---61322851162.pdfIn PDF document text
    • https://jbdclothiers.net/emailer/userfiles/file/6551291537.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/h4l79hrjfbjfk68htrtksqbsi0/nemutowegedosolam.pdfIn PDF document text
    • http://firewheels.pe/userfiles/file/tetovamelifuxi.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/0ft2bjmehejn34ang4jp6bngb0/30381083773.pdfIn PDF document text
    • https://aiwatopup.com/ckfinder/userfiles/files/pugovapimasigidakifo.pdfIn PDF document text
    • https://dakhoathienhoa.net/images/files/10474106751.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a4404b60309---wugokewa.pdfIn PDF document text
    • http://farmaciafici.com/userfiles/files/kawepuzusubudibovol.pdfIn PDF document text
    • http://baohanhranghm.com/upload/img/files/53963744945.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/4d857bfad85ddb3f6302be9c1384a8c7/fanek.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/e9m65sv9hhi053f5qhg83tokg5/gunarobimugadepewuwesuv.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160d3d33374d44---63786273218.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/a1876c7012727d21d0f4df49ad7f424a/72900670590.pdfIn PDF document text
    • https://narimasu-chintai.net/jcfiles/file/xezovamokisesix.pdfIn PDF document text
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/48f5f3f7971ed7ca31aa5e8662d4a8da/faxedore.pdfIn PDF document text
    • http://polish-house.com/uploades/fckeditorfile/kitadudinezuselage.pdfIn PDF document text
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/a293rr3b9kl0g30du03bbrv26p/67123079435.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=i+have+found+chordsPDF 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_off0000c102.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC102 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d914.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD914 17568 bytes
SHA-256: 09771942cfa1510c53c6a2517a1749230b52c9e5b6993b14da3d4e39627c2b57
font_02_sfnt_off0001078d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1078D 10452 bytes
SHA-256: 127b92a0e0e8e15adc7e82c0b3fbf157d3773b693e0dac80cb2fdf7541541ef9