Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a5b420d80671f2c…

MALICIOUS

PDF

75.3 KB Created: 2021-09-09 11:17:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: df57746ce36e4f79e8dcc53aabb69c61 SHA-1: 450deae01eba5808523d02add9fc7ff7cb6dcc40 SHA-256: 3a5b420d80671f2c45fa9ff9c2fe49cb1442680f7f7560dcee069c6952022051
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for delivering malicious payloads. The PDF also contains numerous links to external PDF files hosted on various domains, suggesting it is part of a link farm designed to obscure the true malicious destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

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
  • 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 https://kaparatt.com/images/File/86110489039.pdf In PDF document text
    • http://bestpokeya.com/uploads/files/2996681845.pdfIn PDF document text
    • http://lab4050.com/upload/editor/file/20434985834.pdfIn PDF document text
    • http://vanillasky-ch.com/images/files/1600641418.pdfIn PDF document text
    • http://jn-zhsc.com/upload/29324270578.pdfIn PDF document text
    • http://cp-tournament.org/ckfinder/userfiles/files/dovojenixojivumaz.pdfIn PDF document text
    • http://apcmagon.com/userfiles/74928665315.pdfIn PDF document text
    • http://transcash.com/ci/userfiles/files/80396803789.pdfIn PDF document text
    • http://mvdeastudio.it/userfiles/files/julabubakaruxopivin.pdfIn PDF document text
    • https://floridainvestment.cz/files/file/lerigogidu.pdfIn PDF document text
    • https://www.lsv-wittlage.de/ckfinder/userfiles/files/67741210838.pdfIn PDF document text
    • http://greenlivinggarden.com/htdocs/UserFiles/file/15666042302.pdfIn PDF document text
    • http://draftingfloorplan.com/ckfinder/userfiles/files/89374552857.pdfIn PDF document text
    • https://eletvital.hu/uploads/files/39575385480.pdfIn PDF document text
    • https://bykevin.com/wp-content/plugins/super-forms/uploads/php/files/8b2e4a151ecc687129ac21d3678e22d5/4682326869.pdfIn PDF document text
    • https://onhimalayas.com/ckfinder/userfiles/files/61135720141.pdfIn PDF document text
    • http://devveb.net/userfiles/file/97609424806.pdfIn PDF document text
    • https://cityface.cz/res/file/39515042552.pdfIn PDF document text
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/a551ca57c16461bbeb83563470d22ca2/59972324668.pdfIn PDF document text
    • http://associatedreclaimed.com/userfiles/files/tofipuburulukomiziku.pdfIn PDF document text
    • https://cihangirhotel.com/upload/ckfinder/files/74011816690.pdfIn PDF document text
    • http://dachastyle.com/userfiles/file/44783725326.pdfIn PDF document text
    • http://cuborh.com/natelinhanew/js/ckfinder/userfiles/files/32727387613.pdfIn PDF document text
    • http://taociren.com/upload/file/210907103425759501vfgvfi98aigv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=private+permanent+rentals+jervis+bayPDF 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_off0000c0c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0C4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d8d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8D6 17952 bytes
SHA-256: 310d204e81a3744f4b09169ee22ceea500a0348f55d2a3ca49d4b5ef454941b5
font_02_sfnt_off000106f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106F4 10744 bytes
SHA-256: bc8b13a821140e669369a24218c641507dd2e507b4882a6bb32845dfe6291f08