Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e65d68d8e4c854e…

MALICIOUS

PDF

82.1 KB Created: 2021-06-17 13:06:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 621dccb0951ffeec64e69e9b56072edd SHA-1: eb35d13453d2d2a1c23dc722deb64f37d54cb500 SHA-256: 8e65d68d8e4c854e6c8f7507d8ca14a2fd5b3edaa07f659025f468e169997fc7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised WordPress sites and other domains, suggesting it functions as a link farm or phishing lure. The embedded URLs, such as 'https://coretry.ru/uplcv?utm_term=preposition+questions+and+answers+for+class+10', are likely used to redirect users to malicious content or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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://coretry.ru/uplcv?utm_term=preposition+questions+and+answers+for+class+10 PDF link annotation
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/953b35cdbd1e5d381fc3a99d2df79896/17355748656.pdfIn PDF document text
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b4c9521b351---duledafurowov.pdfIn PDF document text
    • https://www.kcequipment.com.au/wp-content/plugins/super-forms/uploads/php/files/28342bc2ce39b2e511989309f2ff397c/25050530945.pdfIn PDF document text
    • http://wojno-stal.pl/pliki/file/lapoki.pdfIn PDF document text
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/42046e4c0e9c49a0d015d1d2f2aa37ec/85525805623.pdfIn PDF document text
    • http://herculesestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/lotapokunokigisujin.pdfIn PDF document text
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079432b5316e---bavidaliluwoli.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5cad3b275c---78570761610.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1609600a0911e5---repaveg.pdfIn PDF document text
    • https://www.asahinadigital.com/wp-content/plugins/super-forms/uploads/php/files/m28k1i9fouo0n52cd9i6dbucke/diwusekilekaser.pdfIn PDF document text
    • http://rentaruedas.com/files/others/88860939224.pdfIn PDF document text
    • https://everestart.com/images/stories/file/52039829983.pdfIn PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/160aa41debd7ee---34948860808.pdfIn PDF document text
    • https://peterdegendt.be/file/sujofogaxinudopejexujuw.pdfIn PDF document text
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/f635bc733f784d6d547bc75a5d860ed1/96947764682.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010518.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10518 5564 bytes
SHA-256: 65eeb99fb62bfb95eef6157bfebe684a4af02a36fe8098c291bd3411447846d0
font_01_sfnt_off00011828.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11828 10420 bytes
SHA-256: e319d0a22bff3c128f9db9212462101159198bbb6aa716ac379404701b3d67c6