Malicious PDF — malware analysis report

Static analysis result for SHA-256 be669a98e14f80a0…

MALICIOUS

PDF

78.9 KB Created: 2021-09-06 18:23:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 166897e0d9a6c835edba0d809689a379 SHA-1: dc16e3033dafd6e1b41a1e4f9a927c5231383a9e SHA-256: be669a98e14f80a02d556878cff5a8f26753ae0b5af37b402c6e6dd52383459f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous links, many pointing to compromised CMS uploads, suggesting it functions as a link farm. While no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of phishing or malware distribution attempts, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://welltowork.org/wp-content/plugins/super-forms/uploads/php/files/ca787860670558b5696a5e34efb46f4a/92770629561.pdf In PDF document text
    • https://psfund.org/public/uploads/files/cms_files/memarizijobun.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607387483ae7b---38091568160.pdfIn PDF document text
    • https://xn--nmqu14inmf.com/upload/files/dilixewemuzezado.pdfIn PDF document text
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/00f656106d9dba949bae7e239fe4661b/59460242656.pdfIn PDF document text
    • http://aplus.to/userfiles/file/57733036530.pdfIn PDF document text
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/a122f28dde5714069e4acdea7ec8deb2/83667895347.pdfIn PDF document text
    • http://vivatbacchus.hu/files/file/88603936966.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/ad0d506bcdead94f13405343b5a87880/96142289488.pdfIn PDF document text
    • http://guidesdugrandlarge.fr/images/import/file/91569919630.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160878a9cc2024---55182298172.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/45hkkqjuu44fr54iu810975357/1111030021.pdfIn PDF document text
    • http://massageindex.nl/images/uploads/15398050552.pdfIn PDF document text
    • http://archerelectricsupply.com/userfiles/file/luzeguk.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/27e631e181ae3f8629a22bc135c6ab0e/12332437234.pdfIn PDF document text
    • http://atut-biuro.com/uploaded/file/kagixuzin.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/jka4k8uetaaf9tokrt5911s8e1/lakuve.pdfIn PDF document text
    • http://zbraneklapka.cz/ckfinder/userfiles/files/16474392878.pdfIn PDF document text
    • https://aspirans.com/files/file/59135470762.pdfIn PDF document text
    • http://phillipwhiting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160de79be5891e---vulekunowoki.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac2f22e1f92---27717903335.pdfIn PDF document text
    • http://thinhhoanggia.vn/Images_upload/files/65412725340.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608e28d676ce1---30834526426.pdfIn PDF document text
    • http://yljx.cn/images/upload/File/sikevi.pdfIn PDF document text
    • http://lobi.md/userfiles/file/57325534285.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=ubah+file+word+ke+pdf+freePDF 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_off0000d15c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD15C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e96e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE96E 17296 bytes
SHA-256: 06717ea0921fd3886db156ab311b82894c4deeedf688dd88d7a15956f31df788
font_02_sfnt_off0001160d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1160D 10552 bytes
SHA-256: d0c4d07014da7998982fbbb9486975de69a5b8c1aae96a10f8ed302e9ddd0bbd