Malicious PDF — malware analysis report

Static analysis result for SHA-256 21cb5d20aae9a771…

MALICIOUS

PDF

83.3 KB Created: 2021-09-17 22:48:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: b82397152c4d2d59c6545c6a5361ce27 SHA-1: 7b264645a37fdc18c929b9438aa271cc86a71a04 SHA-256: 21cb5d20aae9a771d022dced1eaa76fc5bfcb560db7e262fe07e11b1a7fdd1d3
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many hosted on compromised WordPress installations or disposable domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://pistant.ru/uplcv?utm_term=apk+mod+minecraft+1.13 PDF link annotation
    • http://cesishotel.lv/res/wysiwyg/file/31728864091.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143cc8af4005---vareliwu.pdfIn PDF document text
    • https://metrosecuritynepal.com/assets/userfiles/files/73352391670.pdfIn PDF document text
    • https://ra7a7p-h3ba7.com/contents/files/83864446648.pdfIn PDF document text
    • http://skkl.cn/filespath/files/20210902055546.pdfIn PDF document text
    • http://china-zub.ru/userfiles/file/1022850856.pdfIn PDF document text
    • http://lltsg.com/uploadfile/file///2021091608082099.pdfIn PDF document text
    • http://9262895.ru/ckfinder/userfiles/files/migagudit.pdfIn PDF document text
    • https://sanvexe.vn/webroot/img/files/31046716181.pdfIn PDF document text
    • http://pphu-joanna.pl/fckpliki/file/86144822041.pdfIn PDF document text
    • http://cozycornerexpress.com/uploads/files/zuwediselifaniwopalagejol.pdfIn PDF document text
    • http://marcobernini.it/userfiles/files/18396094139.pdfIn PDF document text
    • http://ghefootmassage.com/fckeditor_userfiles/file/jinosulibufezina.pdfIn PDF document text
    • http://solarexperte.ch/fckeditor/editor/images/file/wenosifuk.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/gn531nipo9n4rb4ubhkvdrbpj2/52358606270.pdfIn PDF document text
    • http://omonetach.pl/foto/ilustracje/file/belenanaseponasokejiw.pdfIn PDF document text
    • https://askisan.com/upload/ckfinder/files/ralulotiviki.pdfIn PDF document text
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132e5d0911ac---16159358059.pdfIn PDF document text
    • http://tagsu.com/attachments/fckattachments/file/86265912043.pdfIn PDF document text
    • https://tkbhanna.com/ckfinder/userfiles/files/zofeliv.pdfIn PDF document text
    • https://chptravel.ir/data/file/58032067003.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/vafofejafuwatenivegonex.pdfIn PDF document text
    • https://minhkygroup.com/luutru/files/gigonusigipure.pdfIn PDF document text
    • http://nyitotthaz.hu/userfiles/files/24993414982.pdfIn PDF document text
    • https://dichvuketoanvn.org/uploads/files/99555555598.pdfIn PDF document text
    • http://cyuanmei.com/userfiles/file/94826522534.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_off0000d70b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD70B 21236 bytes
SHA-256: b3d0f43f9cc6167cb6552b43cc8aac66aedad9298585406314ac6c8b8b8fc3ea
font_01_sfnt_off00010db8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DB8 10928 bytes
SHA-256: 23d5988102ac344eddbd991958e5cf21c8b5c05e3d54ffbb13985702d3ff63b7
font_02_sfnt_off0001271b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1271B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.