Malicious PDF — malware analysis report

Static analysis result for SHA-256 13f49f1c74ae5de7…

MALICIOUS

PDF

66.8 KB Created: 2021-04-28 00:34:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 51640117458b9aa1a56cfefa5ccc5a59 SHA-1: 117a895a752616862b8bcaef4245eddb767f0dc9 SHA-256: 13f49f1c74ae5de74bf01a4bd0d7d05889496ec1607de48e76dc7999f7e13f9d
164 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to distribute malicious files. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery. Although no scripts were directly extracted, the presence of numerous external links and the heuristic findings point towards a phishing or downloader attack pattern.

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://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/160887ee542a0a---67000716663.pdf In PDF document text
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/f0ac19f8932a55d57ceca5f914f977f7/21886189100.pdfIn PDF document text
    • https://lion-trading.co.uk/wp-content/plugins/super-forms/uploads/php/files/l3lq0o4tamnn0j4uib5uieh47i/18615458057.pdfIn PDF document text
    • https://wccia-vastu.com/wp-content/plugins/super-forms/uploads/php/files/29066d9e3a278947d0ae82f1d70e0071/puteboxu.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/bt4jk37obguvs8a3ailed30s6d/dabiwefofevoliroj.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/nitih0upmp44ch4qetb1ivk8c0/fetaralanadinujilez.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/f33d06c64cace727c7b4ed6233b9ea94/1789801975.pdfIn PDF document text
    • http://jjmcp.jp/userfiles/Image/file/72829232291.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/ec5fa764e0ec4603a99865e25917255a/mojelomis.pdfIn PDF document text
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/h6lj6oc5oj4jeap491oge5lk26/xikekepixasojon.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/3f2809a0f1693f87804a25e9c9455caf/togekir.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8daae5a7c---33242740484.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/b128174d4dc18d30c717a8d908497f41/6640296339.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a52bfc6f96---50789887256.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=bter+revaluation+form+last+datePDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c866.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC866 5164 bytes
SHA-256: 4dcce9f86d35ca5f136295059f90ba41ac4a4c9703fc4a96ea3704cedc12dece
font_01_sfnt_off0000d9e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9E9 10736 bytes
SHA-256: 63c9a399beacef239ed0ce87749fdb82c19cba560684b7940f876ee7931bc73e