Malicious PDF — malware analysis report

Static analysis result for SHA-256 4dbfb95b4d0e4040…

MALICIOUS

PDF

72.5 KB Created: 2021-10-09 01:11:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 38eb2db1d9540339177b5f5d31ea6297 SHA-1: 8e104c8f3dc3b6f1a07d4f4c23e4ae4bcddd2912 SHA-256: 4dbfb95b4d0e4040cd2e5f5169d0d28113b0971b2c86f07c772a3540951d9bff
156 Risk Score

Malware Insights

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

The file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Numerous heuristics point to the PDF acting as a link farm, with many external URIs pointing to compromised WordPress sites and disposable domains. These links likely serve as lures for phishing attacks or to distribute further malware payloads.

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://wastran.ru/uplcv?utm_term=essential+mathematics+for+economic+analysis+fifth+edition+pdf PDF link annotation
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/cdb4da74aa5cf834b30a0d2966e2801d/riserefudonixam.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/16151bd3f74480---71349930802.pdfIn PDF document text
    • https://cfaegaianascente.pt/portal/userfiles/files/bonodorasijuxoxefizotaze.pdfIn PDF document text
    • https://menuiserie-sainte-anne.fr/userfiles/file/12675500779.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/28710154760.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16145ceb3481c6---71445531126.pdfIn PDF document text
    • http://kxqcgs.net/filespath/files/20210901110842.pdfIn PDF document text
    • http://neodermclinic.com/file_media/file_image/file/xixegopazaxemikame.pdfIn PDF document text
    • http://vipnjl.com/userfiles/files/44054505493.pdfIn PDF document text
    • https://nonbodepsg.com/uploads/files/2398839655.pdfIn PDF document text
    • http://airconbank.com/upload/fckeditor/file/54209221977.pdfIn PDF document text
    • http://sochi-vitrazhi.ru/ckfinder/userfiles/files/fejenodebalam.pdfIn PDF document text
    • http://rivebistro.net/ckfinder/userfiles/files/vumogifepiwox.pdfIn PDF document text
    • https://hygradeinsulators.com/images/uploads/file/makuguxiwiwikijuwiluvuz.pdfIn PDF document text
    • http://sushrutproctology.org/ckfinder/userfiles/files/99583044509.pdfIn PDF document text
    • http://ogcdc.org/uploads/ck_upload/files/71452901513.pdfIn PDF document text
    • http://zrdb-drogbud.pl/Upload/file/vapegatimawobewula.pdfIn PDF document text
    • https://jewfri.kr/files/image/files/zemopa.pdfIn PDF document text
    • https://nezamirekhaseafoods.com/userfiles/file/7484239482.pdfIn PDF document text
    • https://venusnvs.com/userfiles/file/70267468125.pdfIn PDF document text
    • http://vallovin.it/userfiles/files/82559613742.pdfIn PDF document text
    • http://mawratanews.com/armedia/uploads/files/75393561243.pdfIn PDF document text
    • https://umartravel.com/files/69469349664.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_off0000b8b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8B0 16404 bytes
SHA-256: f4081a6755a47cab9421bb5d6c3f12987d2b2b95fda44abe9f5eda082f92edea
font_01_sfnt_off0000e263.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE263 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fa7a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA7A 10980 bytes
SHA-256: aa19f1e5ee144f482084a37e8589b34040edbb2286b4954649d481d577f5a6fc