Malicious PDF — malware analysis report

Static analysis result for SHA-256 a11b63c81e28d5c4…

MALICIOUS

PDF

73.4 KB Created: 2021-09-22 19:31:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: b38b54ea39347b157bc854a6f899d96d SHA-1: 50ea798a0b7ee77cb4027bb6cfa2e8f9898eb6e7 SHA-256: a11b63c81e28d5c4cf0fa445e50997310ddc1db2e36dde6515a5513109e2207f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a phishing or malware distribution lure. It contains a link farm pointing to multiple external URLs, some hosted on compromised CMS platforms or disposable domains, suggesting an attempt to direct users to malicious content. No scripts were extracted, and the document body was unreadable, limiting further analysis of the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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 http://sunnyten.net/userData/board/file/kemefamoxulu.pdf In PDF document text
    • https://mraos.com/web/userfiles/file/basuzejenarimesidanivi.pdfIn PDF document text
    • http://larrysiegellaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/13100852470.pdfIn PDF document text
    • https://3rproject.eu/ckfinder/userfiles/files/3038027004.pdfIn PDF document text
    • http://jjw-led.com/userfiles/file/vapotolujorafi.pdfIn PDF document text
    • http://thekitchendesignstudio.org/uploads/files/21484198809.pdfIn PDF document text
    • http://hijoin.hu/editor_up/monepusodosago.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/16132fe3180f79---46578754961.pdfIn PDF document text
    • http://leadingedgecorporate.com/user_images/file/rexomenakug.pdfIn PDF document text
    • https://imagebuzz.net/ckfinder/userfiles/files/pojivikusexiwipig.pdfIn PDF document text
    • http://weddingdove.tw/uploads/files/202109140544136777.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/161413ae447195---digawixosomisavolota.pdfIn PDF document text
    • https://nacionalequipamentos.com/ckeditor/uploads/files/25643101825.pdfIn PDF document text
    • https://taperagi.com/contents/files/ginigevi.pdfIn PDF document text
    • https://ssmavidiyar.com/public/content-images/files/16964349665.pdfIn PDF document text
    • https://friendsofmultisport.com/ckfinder/userfiles/files/zisaguminam.pdfIn PDF document text
    • http://explosivedevices.ru/media/file/61951955129.pdfIn PDF document text
    • http://www.hzkontejnery.cz/ckfinder/userfiles/files/5280160830.pdfIn PDF document text
    • http://startmatbaa.com/userfiles/file/15008009481.pdfIn PDF document text
    • http://fuku-zou.com/userfiles/file/vigemaxufujomunizuda.pdfIn PDF document text
    • http://parfumland.sk/upl/mirazedos.pdfIn PDF document text
    • http://myjobcareer.net/userfiles/file/2021091818130473499.pdfIn PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/d100ef1a35200f8e703303c6e57872bb/bulikipikowalidise.pdfIn PDF document text
    • http://tienhasteel.com/app/webroot/upload/files/gizejilexoxuz.pdfIn PDF document text
    • http://asiancfea.org/userfiles/file/84421402691.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=top+game+in+india+onlinePDF link annotation
    • https://www.thc.gda.pl/ckfinder/userfiles/files/73156894512.pdfIn 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://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_off0000be19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE19 10332 bytes
SHA-256: 1772ccb5fc2c2d70a650b489d6868097bc4c268d64fc1b130f91f05134ce0d64
font_01_sfnt_off0000d51b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD51B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ed2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED2D 16628 bytes
SHA-256: bd132bf3962c8ff2e41dcf364e72a41fc93bb83f7687efdf3d5dcc8b341450c7