Malicious PDF — malware analysis report

Static analysis result for SHA-256 b245b4d0f08e5d5d…

MALICIOUS

PDF

81.0 KB Created: 2021-09-17 07:53:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8fb823ef706be54628c9da02bef494cd SHA-1: e43b897037029f30a58f6b0e1f7644ab2b9a65a7 SHA-256: b245b4d0f08e5d5d8f5f9f840ba56aea1d1782cf4c9e76bf61a9d292066287de
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The presence of these links and the overall structure strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://sotel-perm.ru/site/file/84458477920.pdf In PDF document text
    • http://www.gc-antey.ru/ckfinder/userfiles/files/59587999746.pdfIn PDF document text
    • http://koppeika.ru/userfiles/file/77769882362.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161387d3c676da---67828076989.pdfIn PDF document text
    • http://szigmetal.hu/editor_up/86044862716.pdfIn PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b31a33c705---tiluwofozubitovotugata.pdfIn PDF document text
    • http://burbank.kopanramen.com/uploads/files/95875520678.pdfIn PDF document text
    • https://sapporomn.com/userfiles/files/buxajofizakav.pdfIn PDF document text
    • http://umffz21.ru/admin/ckfinder/userfiles/files/3527148772.pdfIn PDF document text
    • https://www.kiemtoandongnghi.com/public/plugins/ckfinder/userfiles/files/84105875990.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/3cg7qtu2mk75n6ql6sk6g60rgu/nuputimogigewevoti.pdfIn PDF document text
    • https://aksukartela.com/images_upload/files/52200045520.pdfIn PDF document text
    • http://newbiesites.com/userfiles/file/31231072808.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/4b91bf98139b5295687c611e6b384590/kejidefukevuza.pdfIn PDF document text
    • http://materialdeestudo.top/userfiles/files/55913359456.pdfIn PDF document text
    • https://ivanda-commerce.hr/userfiles/file/27497590801.pdfIn PDF document text
    • http://emploi.nat.tn/ckeditor/ckfinder/userfiles/files/30929230424.pdfIn PDF document text
    • http://aelma.com/sites/default/userfiles/file/tekefiwekel.pdfIn PDF document text
    • http://samnakthodrahassob.com/userfiles/file/5601815965.pdfIn PDF document text
    • https://www.wroclawmodelshow.pl/ckfinder/userfiles/files/61608863996.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/161414652a8257---mazekoxozoralebobi.pdfIn PDF document text
    • https://proektasis.gr/admin/spaw2/uploads/files/16957688935.pdfIn PDF document text
    • http://lachina.cn/upload/file/54737831570.pdfIn PDF document text
    • http://fcv-bo.org/data/fcv-bo/userfiles/file/zaxufewaziruviluto.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=y+action+wordsPDF link annotation
    • 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_off0000d9d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9D4 17888 bytes
SHA-256: 07c3cd35664ab51fc3fda7b8934967a6c6e166de23d34d793a18499450c7e85e
font_01_sfnt_off0001079b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1079B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011fb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FB2 10252 bytes
SHA-256: d2e8f4b715855c3e2918385edee3c7b739ec37ca54ccb3c318e427d90c4ff687