Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d3d547a6920dd37…

MALICIOUS

PDF

89.4 KB Created: 2021-08-12 13:47:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: cceba5ae36753178e15f0e362b3bfc08 SHA-1: 4250d2f8531e5b231a3b492cf387c8824d5eaf64 SHA-256: 5d3d547a6920dd371c2b0e4752d7b982947792f1a28bda847d49fb986b979a5a
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, which in turn host other PDF files. This suggests a multi-stage attack where the initial PDF serves as a lure to download further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/5d0fdb3e314f62ac51be6503748eda1e/jiditesofubedi.pdf In PDF document text
    • http://xn--12cm8caae5d9a0a0a1dxk6dd.com/user_img/files/fivexozorana.pdfIn PDF document text
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd256129877---22651871908.pdfIn PDF document text
    • http://valeneighbors.com/userimages/84502010598.pdfIn PDF document text
    • https://fwullong.com/upfiles/editor/files/71943843464.pdfIn PDF document text
    • http://dgjst.com/upfile/file/22874868965.pdfIn PDF document text
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609426ce5b4aa---bapafupozibikikupi.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/daxafapovidekamoxu.pdfIn PDF document text
    • https://its-bulgaria.bg/files/file/dinapidatove.pdfIn PDF document text
    • https://clubforeducation.com/FCKeditor/userfiles/file/83894964862.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609b18f27df81---55773385548.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ccbf64ebec1---95368672474.pdfIn PDF document text
    • http://www.videocopilot.net/assets/public/ckfinder/userfiles/files/77214733149.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/160900097229d8---83586223674.pdfIn PDF document text
    • http://innotack.com/userfiles/files/19201921039.pdfIn PDF document text
    • http://sarlampa.ru/upload_picture/matifinamuj.pdfIn PDF document text
    • http://bulgankhangai.mn/userfiles/files/22439953155.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160f8c449b5f30---34244599126.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a368896d8c9---pagemakosi.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/6f42021511369bcebcb8aae2f33d9821/259074579.pdfIn PDF document text
    • http://alkanboya.com/files/file///keparisanidanetiwetoneza.pdfIn PDF document text
    • http://sghscsjamarai.org/guruhargobind/userfiles/file/13523202458.pdfIn PDF document text
    • https://legyenegyjonapod.hu/userfiles/files/18346340342.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/d6c6b8be0f7faa76113c48c40ebfa647/sadaso.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=el+aceite+de+la+vida+pelicula+completa+2%2F3PDF 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f5ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5EA 10780 bytes
SHA-256: 3a253f0939b25d6c0d09a8e46edcb1b21c2ef6f87a0bc4f523afae278daca166
font_01_sfnt_off00010edd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EDD 18264 bytes
SHA-256: 2a74c55f3848e27627daa1e9150dab151b682c9a7f82c97cc60c9eacab3356e2
font_02_sfnt_off00013da4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DA4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1