Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a5035b509d0b206…

MALICIOUS

PDF

77.4 KB Created: 2021-09-13 17:00:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d9f1f4afc61f659377401226783e91dd SHA-1: a131c857b61f1e4e7386135de39cf88fdf387ee4 SHA-256: 3a5035b509d0b20643ac8b2be84e26e4177ee00cb86e1ef107a6bdd36fe6510a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to numerous external URLs, many of which are hosted on potentially compromised or disposable domains, suggesting an attempt to obscure the final destination or distribute malware. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://teplorium.su/userfiles/file/80516408504.pdf
    • http://air-separation-supplier.com/d/files/jovos.pdf
    • http://a899.net/userfiles/file/72410223543.pdf
    • https://luxesystem.site/js/ckfinder/userfiles/files/fenijifegu.pdf
    • http://93564497.com/userfiles/fumimogepolotozidozupekos.pdf
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613366bc4bba3---buwubitorekutanojesanor.pdf
    • https://energiadirect.pl/application/resources/ckfinder/userfiles/files/pelem.pdf
    • http://immobilieninvestors.com/userfiles/file/kapadutexatidod.pdf
    • http://ddaengshop.com/ckupload/files/savupivamesazazari.pdf
    • https://simpangkanan.com/contents/files/57550203995.pdf
    • http://agedwedfjtj.pretty-match.com/upload/files/83615187581.pdf
    • https://jokerprod.net/userfiles/file/57415955659.pdf
    • https://eqonetech.com/upload/userfiles/files/19239366848.pdf
    • https://molecult.metallo-tests.ch/sites/web/upload/files/35235433534.pdf
    • https://catequesisnavarra.org/guiarte_userfiles/files/sugepux.pdf
    • https://cribpointonline.org/cribpointonline/userimages/file/68135528816.pdf
    • http://magnumprint.ru/upload/files/xaputogonusuri.pdf
    • http://akcjonariusz.com/UserFiles/file/nuwasunefotikeguwe.pdf
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/16132a612dd875---83785523543.pdf
    • http://iowatriallawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jiwipedaxode.pdf
    • http://abarappresentanze.it/userfiles/files/47598432572.pdf
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613206f17524a---xowoful.pdf
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/5nc6borpla1be4oungbqoskcm9/88060171301.pdf
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/161313c1301081---67301328526.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=free+fortnite+on+android
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cb40.bin
7b422090e9e678832f0e39f23ada440e3d1f90331598123c486be38494b48d40
pdf-font-stream PDF embedded font (sfnt) at offset 0xCB40 10112 bytes
font_01_sfnt_off0000e1e5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE1E5 16792 bytes
font_02_sfnt_off0000f9f7.bin
81697ee46e78facba00514fc22369bfbb35dbacdcf737de16d01dd0c8a47ac8d
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9F7 17860 bytes