Malicious PDF — malware analysis report

Static analysis result for SHA-256 8db08d5d53b3e949…

MALICIOUS

PDF

71.3 KB Created: 2021-10-01 02:03:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9640ec7d8e8301cb50df32f6a975d671 SHA-1: 59262ae2eb6bd8c75a76c14d4c5f4d828b59c9cb SHA-256: 8db08d5d53b3e949bb461d1cba8bb8dd87b61f3435ab6a5f319029fc8d1846c0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of external links, many pointing to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and numerous URLs are indicative of a malicious document, potentially leveraging embedded JavaScript for redirection or further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://cructi.ru/uplcv?utm_term=samsung+a02s+custom+rom
    • http://theartofdesign.nl/ckfinder/userfiles/files/bepilanopavarigi.pdf
    • https://biomisszio.hu/tmp/61430757073.pdf
    • http://klick-tipp.info/ckfinder/userfiles/publics/files/zufevakadofabe.pdf
    • https://perfecthospital.net/FCKeditor/file/44895880430.pdf
    • http://sakuragiramenandsushi.com/uploads/files/folerunumije.pdf
    • http://anthonyjcincottalaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/napokir.pdf
    • http://hstairan.com/FCKeditor/editor/filemanager/connectors/php/userfiles/file/sutisazevarufatez.pdf
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161391a81b75bc---wadafi.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16155abee5d02b---85315006831.pdf
    • https://jin-hung.com/userfiles/file/dosonu.pdf
    • http://homeopathyhongkong.cn/files/77268781403.pdf
    • https://eastmangroup.org/ckfinder/userfiles/files/41242744762.pdf
    • https://damiel.eu/userfiles/file/19417607757.pdf
    • http://laduses.nl/image/file/mubofajaka.pdf
    • http://shipagents.nl/uploadfiles/file/joperivamesovorubemeg.pdf
    • http://netmutum.com/userfiles/file/zovun.pdf
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16139eeeb5248b---nebifibovumelopiv.pdf
    • http://wskinbody.com/data/boardData/files/27335974424.pdf
    • https://beylikduzutabelaci.com/userfiles/file/wazuvuretojojobu.pdf
    • http://ohxto.com/uploaded_files/userfiles/files/fekebivejatulotoligodije.pdf
    • http://djarkitek.com/temp/vinney/HTML/userfiles/file/toxefevadexesel.pdf
    • https://demo-calson.garment-pro.com/ckfinder/userfiles/files/divesesalunuto.pdf
    • http://www.anclupnapoli.it/userfiles/file/ragezujexuve.pdf
    • http://tc-muehlacker.de/data/tcmuehlacker/userfiles/file/zaxipajela.pdf
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/783b03b03dc247f0a065fabd6d117e2b/sudamov.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b129.bin
543be79b1cfaedca19ae8af54a6d044653b0ca359ef60bb5304cd2523f3aac4c
pdf-font-stream PDF embedded font (sfnt) at offset 0xB129 17288 bytes
font_01_sfnt_off0000dd8e.bin
4f0b4999620c66373810b7bbe82acb7302c27bec2fdbfafbc09efe18aca476b9
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD8E 10720 bytes
font_02_sfnt_off0000f63e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF63E 16792 bytes