Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff116e0fdc5dba4c…

MALICIOUS

PDF

90.2 KB Created: 2021-06-13 01:29:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: b124661ef0ef2ea60f6576680f8ad453 SHA-1: 2d5ab5cafb6f9ef28967b9a41d570d418cf61a1e SHA-256: ff116e0fdc5dba4caeb59ada171f8ed149f78f90f60ff00d0fae73a2b32a61b1
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • 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://synerhu.ru/uplcv?utm_term=pharmaceutical+jurisprudence+mcq+book+pdf PDF link annotation
    • https://gradeagroup.com/wp-content/plugins/super-forms/uploads/php/files/8s37mmljf4polb1en994hv1j5o/fofedodejenebefunifipu.pdfIn PDF document text
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a74a047f05a---17071558965.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/d18pq6f7rpk54arng1o8foo7cp/3319140811.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607eaed76cd3f---3178373321.pdfIn PDF document text
    • https://banghenails.com/upload/file/24633155103.pdfIn PDF document text
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/a6fbdc65b94c0918ae062b5a53e9ec4f/50033951921.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/df2c2568b2184e5d0cacdfd212ff1e78/gupiloxitemarunu.pdfIn PDF document text
    • http://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/6d5d90bc50d592922c2848b3180154d3/momekemejibale.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6c18d9017c---47834894653.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/16076e2140731e---fukodesupif.pdfIn PDF document text
    • https://www.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/cd9r1ehss506hvtgdtefluvk4l/zaketukapesunaloz.pdfIn PDF document text
    • https://georgiamusicpartners.org/wp-content/plugins/super-forms/uploads/php/files/8385f6e5624e4b1babcd53d30b41204e/notugedejumu.pdfIn PDF document text
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b06fcb77b44---netuxoxopazixibavojex.pdfIn PDF document text
    • http://thamdinhgiadaiquang.com/img/files/morepuwepotokenunezubu.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/1607b889c1da57---zefarozejev.pdfIn PDF document text
    • https://adlinefor.com/home/webagen/public_html/korn/data/file/54688848824.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/9ed7d118472e05a6400e555691ff8ebd/56083775140.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011f4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F4D 5804 bytes
SHA-256: 1bc9727c942df17ce64623cf620ba9401de120141a225dc2dac97d6eec82f46f
font_01_sfnt_off000132dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132DC 11548 bytes
SHA-256: f48910f8ab794e9c527b684a398a3936b61405095716e9741b21a5bfa36a3d55