Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9e1d1f98e4cd11b…

MALICIOUS

PDF

89.9 KB Created: 2021-10-14 12:44:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 1bbdcc06ca04d71073b208782bd2562e SHA-1: d2d4788892e6ec4256ae27db3868aa271709b724 SHA-256: c9e1d1f98e4cd11bd60a53236afb2ee1adaa55b9af0b2bcd714045730b89f45f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://crysiq.ru/uplcv?utm_term=3+different+methods+of+heat+transfer PDF link annotation
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1613e09c91ad2e---lixubenizupunoz.pdfIn PDF document text
    • http://maketmaster.ru/admin/ckfinder/userfiles/files/69969976405.pdfIn PDF document text
    • http://xn--j1aii.su/userfiles/file/92427558437.pdfIn PDF document text
    • http://mebelhotel.ru/userfiles/files/1304608927.pdfIn PDF document text
    • http://chukguwang.com/files/fckeditor/file/gurukav.pdfIn PDF document text
    • https://habibitoursegypt.com/ckfinder/userfiles/files/57561724462.pdfIn PDF document text
    • https://yapluka-services.fr/userfiles/file/nidewokutexewegil.pdfIn PDF document text
    • https://songiadahoaian.com/upload/ck/files/93034703843.pdfIn PDF document text
    • https://texigo.tw/upfile/files/2021/09/04/58443424638.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613f66bb77695---dobojevawamimotudef.pdfIn PDF document text
    • http://www.musicboxpiano.com/contentfiles/90651082778.pdfIn PDF document text
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/b088cfce113bfe1afa428307b68d30d8/vuwemaferewomef.pdfIn PDF document text
    • http://girlstown.org/files/js/ckfinder/userfiles/files/vimitudujir.pdfIn PDF document text
    • https://sassanoproperties.com/FCKeditor/file/29108530504.pdfIn PDF document text
    • http://j1medical.com/uploaded/file/10310164404.pdfIn PDF document text
    • https://sca-eagleegg5k.com/ckfinder/triplebuserfiles/file/22044737833.pdfIn PDF document text
    • http://daejonggyoyc.com/userfiles/file/20210921225505.pdfIn PDF document text
    • https://ms2gacor.com/contents/files/14743362934.pdfIn PDF document text
    • http://scissortailfarms.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a82ff829a4---79413419246.pdfIn PDF document text
    • http://sungder.com/upload/tagisinameloveterur.pdfIn PDF document text
    • http://arqing.es/ckfinder/userfiles/files/sasil.pdfIn PDF document text
    • http://dhf-china.com/d/files/datiwopowafuzozupawu.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_off0000fb66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB66 18000 bytes
SHA-256: bc62a80fa9c742953e7765c31a545a84d6300b302d87810091e39bad1b9b8ea4
font_01_sfnt_off000129f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129F2 10648 bytes
SHA-256: 3e60d84f8b297f3df1ef19c2dd6f2f8e8b05e93081ace6883fa595c649138aa2
font_02_sfnt_off0001421e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1421E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1