Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c8c5f155571836f…

MALICIOUS

PDF

76.6 KB Created: 2021-09-18 10:13:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: d566f6f1f271826f88a7f69aca309986 SHA-1: 2f61f7174374a2189189653d6a6b6bd972a831b0 SHA-256: 9c8c5f155571836fe0a916c5c1106aa66795b69ba3e031201742365569bee4c1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or trojan threat. It contains a link farm with numerous URLs pointing to potentially compromised or disposable hosting, suggesting an attempt to distribute malicious content or phish users. The presence of external URIs and link farms indicates a likely spearphishing attachment vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://arnoldbolingbroke.com/ckfinder/userfiles/files/josog.pdf In PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/1613647dfe88f5---tolodufumalixurowe.pdfIn PDF document text
    • http://lab4050.com/upload/editor/file/banikosubizukanetive.pdfIn PDF document text
    • https://sindonis.com/userfiles/file/gomodaza.pdfIn PDF document text
    • http://unseretochter.com/images/file/14291694864.pdfIn PDF document text
    • http://beiwendq.com/userfiles/file/buxop.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/5d9dc7fe955fbbf9edf6a06839f06e1d/85139423376.pdfIn PDF document text
    • http://cheers-gifts.com/userfiles/jefomakebaniwimuposavo.pdfIn PDF document text
    • https://tahuacoop.com/cms_gpadmin2015/sgi_userfiles/userfiles/files/fixubajofidozejesa.pdfIn PDF document text
    • http://sllight.ru/design/img/upload/file/67637480923.pdfIn PDF document text
    • https://borgopitti.it/userfiles/file/narojikunosizalinemawu.pdfIn PDF document text
    • https://negaratoto.com/contents/files/relegujeb.pdfIn PDF document text
    • http://melvin.cz/data/74129556587.pdfIn PDF document text
    • https://tutorbolivia.com/userfiles/file/siwaxedovemif.pdfIn PDF document text
    • http://poney-club-romilly-aigre28.fr/userfiles/file/vudovoriwoxoremimided.pdfIn PDF document text
    • http://dj-maily.com/uploads/pages/files/98772334443.pdfIn PDF document text
    • https://comptables-publics.fr/userfiles/file/9782738398.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/00ee8c150b1c2b204fa13d4d9759e12b/19558584092.pdfIn PDF document text
    • http://hanasushimenifee.com/uploads/files/nesukijidugomuzixunaw.pdfIn PDF document text
    • https://sensesgrouphk.com/louis/STARKGROUP/ckfinder/userfiles/files/89120400398.pdfIn PDF document text
    • http://kanomax-nsk.ru/images/fudemowabafexifisoperazar.pdfIn PDF document text
    • http://sten.kr/club/data/userfiles/file/20210907144426.pdfIn PDF document text
    • http://danies.ru/ckfinder/userfiles/files/tokupusafavunelixupoza.pdfIn PDF document text
    • http://ruizhishengwu.com/uploadfiles/file/16233256906.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=how+to+take+screenshot+of+restricted+appPDF 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_off0000c6f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6F7 10840 bytes
SHA-256: 9adc6a62bca0a282b7b0e647b36bf20cbd324306195866604e9ac35efa478be1
font_01_sfnt_off0000dffb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFFB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f80d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF80D 17180 bytes
SHA-256: e92feada924f063c714e06189b97d40fb76e22c2ea73ee571760f383a73ac462