Malicious PDF — malware analysis report

Static analysis result for SHA-256 e8a51f7275285926…

MALICIOUS

PDF

75.6 KB Created: 2021-06-14 05:26:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: da7dad6b94d10df2cc1b9ce789d23cb4 SHA-1: 71de82a2f20c7cbda63ba7a80c71b3dd772d6477 SHA-256: e8a51f72752859262be8320d2ce222bced9a0b33b38cc9a71ed8be23a5d3239c
156 Risk Score

Malware Insights

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

This PDF document contains a link farm pointing to numerous compromised WordPress sites, likely intended to lure users into downloading further malicious content or engaging in phishing. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it's part of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://wastran.ru/uplcv?utm_term=6+class+math+question+answer PDF link annotation
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bd33e79a784---26012267147.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/0d706d65e03fbb9a60abca1f5b30284e/vemufinidonetefu.pdfIn PDF document text
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/90a80016950c718fca5fcae869ab81d5/senokijanubelupuv.pdfIn PDF document text
    • http://al-bandak.com/userfiles/file/67033998410.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b510ec26b97---texutepa.pdfIn PDF document text
    • http://mdsalon.ru/img/lib/file/lugus.pdfIn PDF document text
    • https://nikken-engineer.jp/export/sd205/www/jp/r/e/gmoserver/8/6/sd0748886/nikken-engineer.jp/fckeditor/upload/file/pakipeduza.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a07c806f80---keremanomagidomaregamexi.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160997423afdde---fokivujer.pdfIn PDF document text
    • https://pointsourcegroup.com/wp-content/plugins/super-forms/uploads/php/files/cdfcb8b3aff432d457b46cf2c011e14a/widubenatasebosutur.pdfIn PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a2d1d6bb6c6---baxolodusosikakozifoxage.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/5md43lbobj5pphcouofpptuj4a/puzuroginud.pdfIn PDF document text
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/cfii5f6du38sre94da6d6ltton/vider.pdfIn PDF document text
    • http://sklepjola.pl/userfiles/file/vuxupepop.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/nca7lqoc680edcagn8h4fsb2t5/wovepegubapigeguje.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_off0000e9ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9AD 5316 bytes
SHA-256: 70a1f2761ef2b76087cbb27c1fbe4583ac890fc033b4ca8b2b3a1551af584b68
font_01_sfnt_off0000fba7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBA7 11052 bytes
SHA-256: a2fd1e2fb7726e416b76de4b4c94c14faf3da187346ff13d932faf10884a982d