Malicious PDF — malware analysis report

Static analysis result for SHA-256 f66efb0b07a99e42…

MALICIOUS

PDF

117.8 KB Created: 2021-09-06 19:53:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: cf187af893a86beeca0ee880349e0927 SHA-1: 1a1c4a5b3b371426ce1d34b433951485e7278a63 SHA-256: f66efb0b07a99e421317d9a4e55b40c7166e99dc2bfb19b67034e59164edc0e7
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to distribute malicious content. ClamAV detection and ML classification strongly indicate malicious intent, likely for phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://crysiq.ru/uplcv?utm_term=line+6+micro+spider+user+manual PDF link annotation
    • http://archpiudue.com/userfiles/files/7902621049.pdfIn PDF document text
    • http://interroadholland.nl/userfiles/file/60006907626.pdfIn PDF document text
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/2a3059c9c0ab90d68e363e97f37a7af7/29794142131.pdfIn PDF document text
    • http://fandimnarodaku.cz/upload/file/xadokodamuvo.pdfIn PDF document text
    • https://brod-plovdiv.com/images/juforoborisuneravi.pdfIn PDF document text
    • https://curewelldiabetes.com/userfiles/file/furubofusogogawisiwaxizez.pdfIn PDF document text
    • https://rajatotogroup1.com/contents/files/wibemikutegibevi.pdfIn PDF document text
    • https://www.gurgy.net/ckfinder/userfiles/files/motomoxatezamugemegatajuz.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/minatusumusi.pdfIn PDF document text
    • http://www.zaluziemalina.cz/userfiles/file/33165304116.pdfIn PDF document text
    • http://autoset66.ru/admin/ckfinder/userfiles/files/muxukofunaxukogut.pdfIn PDF document text
    • https://dycmc.com/DATA/upload/files/202109010147271477.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160c39e4858644---wusoj.pdfIn PDF document text
    • https://dortmundpools.com/contents/files/giwidotejerisalapanem.pdfIn PDF document text
    • http://mottaing.eu/userfiles/files/xivisanevogijejimuba.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/xexovudagiwisuwatitudidin.pdfIn PDF document text
    • https://sharjahcements.com/images/bulk_images/files/mizenomurivumosolamazuva.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/rm6knnfj9iauldq6pt57bh2hof/65565378753.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098be302272c---xapawunafuzegokedexuv.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/928a407e5f6c55cf64f9ddfd371d1e7c/kubugujipavifit.pdfIn PDF document text
    • https://reha.bg/content/upload/file/romukusefo.pdfIn PDF document text
    • https://realestateconnect.us/wp-content/plugins/super-forms/uploads/php/files/5l3mrsr3tjgqi62t005vdal7s2/21214135457.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_off00016494.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16494 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00017ca6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17CA6 19980 bytes
SHA-256: 7d2a4d2e8e1a3d0bdf74117da31a1825949c1ac06820b37bc7a9bfa6d5830076
font_02_sfnt_off0001b0a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B0A9 10800 bytes
SHA-256: 9c8be2b413182ad835251c76e0379829f776a4fbf69ce21ef41bc65f093e6466