Malicious PDF — malware analysis report

Static analysis result for SHA-256 6db351289c024960…

MALICIOUS

PDF

86.9 KB Created: 2021-09-19 13:23:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: b5622093a494d767a9416b8c24728ac0 SHA-1: bbf99c29dda53d2a4f97876f17162e14c88bd7ce SHA-256: 6db351289c024960120151f43f1a7ff2859abac80a92a4c07de3ec5d012c9eac
156 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and links to compromised CMS upload storage, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristic findings point to a malicious link distribution pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://krisoc.ru/uplcv?utm_term=battle+isle+android PDF link annotation
    • https://bhopalliteraturefestival.com/mpsdp/uploads/files/54208434720.pdfIn PDF document text
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/211035553f38f15a80b88c8a079ab66e/87507170005.pdfIn PDF document text
    • https://nawaasha.org/userfiles/file/lidolukosogevex.pdfIn PDF document text
    • http://titusauto.hu/kepek/file/28774975324.pdfIn PDF document text
    • http://ozhelalikram.de/resimler/files/ginaxifot.pdfIn PDF document text
    • http://greenhousehotel.vn/uploads/image/files/lazameraxozume.pdfIn PDF document text
    • http://easytravel63.ru/ckfinder/userfiles/files/95633233870.pdfIn PDF document text
    • http://upnbkk.com/file_media/file_image/file/11240349108.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/djhmf6b1m9qbrejrdupca1hopg/76840879848.pdfIn PDF document text
    • https://foodphotoshop.com/userfiles/files/vonomiwujunop.pdfIn PDF document text
    • https://etcbt.com/userfiles/file/8133663949.pdfIn PDF document text
    • http://www.astmalek.cz/obrazky/file/vanimewigetuw.pdfIn PDF document text
    • http://www.dialog-seversk.ru/jsplugins/ckfinder/userfiles/files/24897191612.pdfIn PDF document text
    • http://bookblog.kr/data/file/files/tiforow.pdfIn PDF document text
    • https://pataniforum.com/admin/jquery/ckfinder/userfiles/files/52547302078.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161417b4e4fea9---gerajivosogifuzotinigofoj.pdfIn PDF document text
    • http://ecolservizinettuno.com/userfiles/files/zowowe.pdfIn PDF document text
    • https://micsys.in/userfiles/file/dinubivas.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b4ab4450aa---gerugexiradusufe.pdfIn PDF document text
    • https://zahrek.com/userfiles/file/2929739910.pdfIn PDF document text
    • http://med-os.com/user_upload/file/tegej.pdfIn PDF document text
    • http://dorrstrechy.cz/UserFiles/File/47524083844.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/bobobu.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_off0000f03e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF03E 10292 bytes
SHA-256: 22a731cb39ceb6976f12981b3193a06bdf9363a7a13ed5c6c463377c545d261c
font_01_sfnt_off00010791.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10791 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011fa3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FA3 17344 bytes
SHA-256: 6040b4d24211e07ab8aa80711dc920ed867f886015dfbcf000392af6421538d1