Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a005e405cf0400b…

MALICIOUS

PDF

76.4 KB Created: 2021-06-09 22:17:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 3b2bbafb3c4d3177762776fdb82f2df2 SHA-1: 6da0186a27933591ff8e68f1247d6389833e0d9c SHA-256: 4a005e405cf0400beb7fcb75164825a8178b5bbc394a6a2822e95bd76db05526
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-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.
  • 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://chcial.ru/uplcv?utm_term=english+grammar+textbook+for+class+7 PDF link annotation
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/160bfc54e2dc12---tofatuneb.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608030063f522---32407522232.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/b0ebf4420df880989637f327c369299d/55917555117.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/160795b1acb637---varanazom.pdfIn PDF document text
    • https://sjalikave.hu/pictures/file/nomobivagojagukezekisuz.pdfIn PDF document text
    • http://niestachow.pl/data/aktualnosci_imgs/file/kojifuxolovefoposivafonu.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5c9ad31240---lidagovexuvava.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3ae14cb079---wopopada.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160821ca146c66---vatakowegopod.pdfIn PDF document text
    • http://www.asslar.de/downloads/27756806335.pdfIn PDF document text
    • http://alnoorcity.com/userfiles/file/2380507968.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/tabomvv8cugauono1gdi6knav1/bubiponixaguxonofe.pdfIn PDF document text
    • https://krimgranit.ru/wp-content/plugins/super-forms/uploads/php/files/7d6cc2214e5334c04f02afddd58c1f43/tolojapususu.pdfIn PDF document text
    • http://strandedtattoo.net/file/lojekolediruf.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ddaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDAA 5392 bytes
SHA-256: c6c0cb146d1443e482e2f63997272290b34a5bb0f83a6ee69d99aeb0b1e9214b
font_01_sfnt_off0000efd4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFD4 10988 bytes
SHA-256: 7ed3f5d0951807dfd30f7a787e178a2b5a9e7b629efc1b9beb0cbcb65c32616a
font_02_sfnt_off00011504.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11504 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3