Malicious PDF — malware analysis report

Static analysis result for SHA-256 f9b5a95b549d7b08…

MALICIOUS

PDF

80.5 KB Created: 2021-06-15 10:55:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: b230188761e089ea89b05c10c51f39f2 SHA-1: 98727f70d380718c1a4a2080f4df2722beaa7139 SHA-256: f9b5a95b549d7b0830622eda4471b26f4ddfa1b0738cb2f3570631c52afdd72e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. The document contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the overall structure point towards an attempt to exploit users' interest in free content to deliver a payload or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://krisoc.ru/uplcv?utm_term=read+nora+roberts+online+free PDF link annotation
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/50781621802.pdfIn PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/c13f5ccde841467a13d4fbc7f7e064c0/76150628870.pdfIn PDF document text
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/e47ji6fvilcimepemmb2du7khc/bajuwexa.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/160739c632c195---9246848660.pdfIn PDF document text
    • https://bechtoldpaving.com/wp-content/plugins/super-forms/uploads/php/files/af160d493fb642a0407c36e87fcc3086/92206444359.pdfIn PDF document text
    • https://naucharts.com/ckfinder/userfiles/files/2384631563.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/9ceebb3632bc38f19aed21721db7817d/44141868179.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/f36ed922d86d75c2f688c06b61dcedce/68263055251.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160c84f2e5d088---15963512820.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b3005934959---silutobumavuwogijosov.pdfIn PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16088047020852---rimus.pdfIn PDF document text
    • https://aduanaldelvalle.com/userfiles/file/femelewukudedupikob.pdfIn PDF document text
    • https://kitapkaplama.com/upload/ckfinder/files/fupukivuwadawanekew.pdfIn PDF document text
    • https://butchercurnow.com/img/shop//contents/66917754264.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/ba087ef44299dad3683aa50cd2ea1102/70439993825.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_off0000f125.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF125 4836 bytes
SHA-256: db58b941a0752f3d6dafcc145f7d734886d9923ece98d44417d759cb3533d376
font_01_sfnt_off0001019a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1019A 10948 bytes
SHA-256: 93821807b597441a7db72ed2e3319b48f2dc8d1308e56fd434eb01d94349621e
font_02_sfnt_off00012709.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12709 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3