Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a58fd88ab0cf8d6…

MALICIOUS

PDF

75.1 KB Created: 2021-09-10 07:05:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: bf1428722a0649a74b2567b9ddd9b6e2 SHA-1: cfbb980c8b4a4eb7f690d63eaba6a590f7c2f239 SHA-256: 3a58fd88ab0cf8d61748aa162555cf15ac5adf0745f766381a4468c32feb4c1f
134 Risk Score

Malware Insights

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

The PDF contains numerous external URIs pointing to disposable domains, indicative of a link farm designed to host malicious files. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' confirms the use of multiple distinct, low-reputation hosts for hosting PDF files, reinforcing the phishing or malware delivery vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://irlanc.ru/uplcv?utm_term=new+2004+tamilrockers PDF link annotation
    • http://dlzhrjd.com/images/uploadfile/files/46136601079.pdfIn PDF document text
    • http://mediedil.eu/userfiles/files/58867028040.pdfIn PDF document text
    • http://texinpack.com/uploadfile/file///2021090914442623.pdfIn PDF document text
    • http://de-ko-gmbh.com/ckfinder/userfiles/files/futubowuropubulaniden.pdfIn PDF document text
    • https://www.alugutader.fr/ckfinder/userfiles/files/nevonifopiriliduzodegoza.pdfIn PDF document text
    • https://www.oalysa.cz/ckfinder/userfiles/files/guvafenipoworilela.pdfIn PDF document text
    • https://www.weboonline.com/ckfinder/userfiles/files/59374885568.pdfIn PDF document text
    • https://defi128.com/userfiles/files/92830728370.pdfIn PDF document text
    • http://k-sta.kr/FileData/ckfinder/files/20210909_5DA1C3476E42CC19.pdfIn PDF document text
    • http://thestarbusan.net/FileData/ckfinder/files/20210909_54F0B6FDDF3AE9E0.pdfIn PDF document text
    • http://eko-gospodarstwo.eu/files/file/veritagizaxeveguxikison.pdfIn PDF document text
    • https://semsaesp.com/ckfinder/userfiles/files/49952897268.pdfIn PDF document text
    • http://www.premiumimport.nl/ckfinder/userfiles/files/kumojiwuzojonomilopixabo.pdfIn PDF document text
    • https://akilanews.com/ckfinder/userfiles/files/58760233427.pdfIn PDF document text
    • https://istanbulbalbir.com/upload/ckfinder/files/gaxuxuluwujujurud.pdfIn PDF document text
    • https://pabxlg.com/userfiles/file/tobebaneb.pdfIn PDF document text
    • http://geometrabottero.it/userfiles/files/27031236117.pdfIn PDF document text
    • http://fabtur.ru/upload/files/73193081463.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613aa433ae422---12524653742.pdfIn PDF document text
    • http://kronospan-mofa.hu/editor_up/favuwapinujisexo.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/q1gd5ibot6969ohfiuls0qpg21/56921865143.pdfIn PDF document text
    • http://mikailang.net/userfiles/file/20210906003826_732657658.pdfIn PDF document text
    • http://www.siscbolivia.com/admin/uploaded/fck/file/68193280081.pdfIn PDF document text
    • http://canadianartistic.com/userfiles/file/50862557035.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_off0000c0a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0A3 10764 bytes
SHA-256: d5ea0b51cc61ce0444f0dfe88f1ebb91b52f3bf724abec2d82a78dc74678c1cc
font_01_sfnt_off0000d992.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD992 17560 bytes
SHA-256: 5178c666b58ff63de76e91c4ee7e42f865494a2d1fd68661a8e4bc1f520b460c
font_02_sfnt_off0001072a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1072A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1