Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb4291736f810e4b…

MALICIOUS

PDF

77.4 KB Created: 2021-06-15 14:07:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 6d3c13d4e1b3f0d6b1c1e60f854ed7df SHA-1: 08002569d0ef9cd1d2dc98ea0ee0a16d959ed56e SHA-256: fb4291736f810e4b9aedb40f28899ee1255388d374ed3db813f11b896ca6e07a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF document contains numerous links, many pointing to compromised WordPress installations, suggesting it's designed as a link farm. The presence of 'utm_term' parameters and the structure of the URLs indicate a potential phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly support its malicious nature.

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://crewmak.ru/uplcv?utm_term=red+eyes+deck+yugioh+legacy+of+the+duelist PDF link annotation
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a61c75b1ee---bonalenofemasotuzuxara.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fb391a122d---lowogorozizopexubu.pdfIn PDF document text
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a4ce66acde5---nuwimabomomuvabi.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/br3tm6bnljqtj1va1nsget50ld/27006026337.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b608f56d339---kuxerebikozozivikarogure.pdfIn PDF document text
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/ab92ee5720cc7abd8d8ea35228e85003/24420296107.pdfIn PDF document text
    • https://asiarsolutions.com/userfiles/file/35389270076.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16076ed8d88a2b---97456594672.pdfIn PDF document text
    • https://www.engltg.com/wp-content/plugins/super-forms/uploads/php/files/b10ad8565b3432ea4f206b44733c819e/95498604664.pdfIn PDF document text
    • https://aljazeerahpetroleum.ae/userfiles/files/solurolokorifawavifeputeg.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1609643ab26b4a---36464202371.pdfIn PDF document text
    • https://cowichanseniors.ca/userfiles/file/dozume.pdfIn PDF document text
    • https://diedacorporation.net/freesiafiles/file/xofefuv.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/9a384a42abe65e2f9e763eabe8e9f924/39711174551.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e647.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE647 2900 bytes
SHA-256: b3dfb2f2c41da7350fc3755141d2fd0ea5796bb125df25fec831093623ff73df
font_01_sfnt_off0000f08a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF08A 5360 bytes
SHA-256: bdd71efb26bf82a2aae3b942bc7980d3ca3722c513fae87dfe06b29d5cda19f4
font_02_sfnt_off000102de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102DE 11052 bytes
SHA-256: 305266c6d1feac284cbef763b88e2d9bcf4a12059b74ced5cc8eba1e68ed0598