Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4e23996bac15962…

MALICIOUS

PDF

87.2 KB Created: 2021-09-21 02:55:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 3da74a7e291967ad7029d10c5c20de55 SHA-1: c2ff3de272b68ba3b2b99184abca6f8721563f96 SHA-256: c4e23996bac159620d74338a6bca7db24539c0af79bbe89c82f310bc05664381
156 Risk Score

Malware Insights

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

The PDF was flagged by multiple heuristics as a link farm and by a machine learning classifier as malicious. It contains numerous links to potentially compromised websites, suggesting an attempt to direct users to malicious content. The ClamAV detection further supports its malicious nature, identifying it as Pdf.Phishing.Trojan.

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 http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145adab29aed---50044914330.pdf In PDF document text
    • http://taiwangallant.com/uploads/files/202109041624058250.pdfIn PDF document text
    • https://elpollopaulino.com/cenavarra_userfiles/files/77755024357.pdfIn PDF document text
    • http://alisawedding.com/upload/users/files/32145978177.pdfIn PDF document text
    • http://galluccifaibano.com/userfiles/file/7840664838.pdfIn PDF document text
    • http://www.goldenlantern.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161430ef453c8f---mofojapevototikaxevawi.pdfIn PDF document text
    • http://logtech.cz/foto/Image/file/69587507777.pdfIn PDF document text
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/7qbj63vdhc617i9p0j5uutm0d4/83125681614.pdfIn PDF document text
    • http://geoman.cz/data/file/69654342115.pdfIn PDF document text
    • https://zevkotodoseme.com/upload/ckfinder/files/xekexuvuderufiwiboked.pdfIn PDF document text
    • http://bluebirdcanada.com/FileData/ckfinder/files/20210908_25AE0FC0C9B4D5E1.pdfIn PDF document text
    • http://ineke-ott.nl/keramiek-beelden-imagesfile/nuxafusovitobodifefeb.pdfIn PDF document text
    • https://wildnaturetravel.com/File/2634988494.pdfIn PDF document text
    • http://mayinmaunhat.com/upload/files/3864227707.pdfIn PDF document text
    • http://kozszemle.hu/uploads/files/86741710440.pdfIn PDF document text
    • http://nguyenthaotech.com/upload/files/dapurufepagoxineloki.pdfIn PDF document text
    • http://crestviewshopping.abwingsmd.com/uploads/files/koredakotagepi.pdfIn PDF document text
    • http://vektor28.ru/userfiles/file/44779367613.pdfIn PDF document text
    • http://aerotherminsulation.com/userfiles/file/xabijisolitupiteju.pdfIn PDF document text
    • http://wingmanplanningdemo.com/userfiles/files/wofixewumazebuvejaruboxuw.pdfIn PDF document text
    • http://idrogastermoclima.it/Utentifile/FCKPage/file/luxuten.pdfIn PDF document text
    • https://smartbrand.ro/mm/file/paseze.pdfIn PDF document text
    • http://imoroz.by/upload/file/lofoladokosuwidavibog.pdfIn PDF document text
    • https://digireg.at/upload/nerezuvokusovejejimoxawas.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=the+walking+dead+season+11+streaming+freePDF 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_off0000ec97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC97 18748 bytes
SHA-256: 57d603896b9fec57d158974365f0225bc906cb3b799e5fc48cb602cc149e7a03
font_01_sfnt_off00011d48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D48 10996 bytes
SHA-256: 56bfcba8cbcd1180d00cf4a98ae8177ed56ce852c6b377dbe8861fabff30bf82
font_02_sfnt_off00013689.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13689 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1