Malicious PDF — malware analysis report

Static analysis result for SHA-256 cab19b0bd63bc2bf…

MALICIOUS

PDF

84.7 KB Created: 2021-09-17 03:06:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 590466feae1014a13a9aeaec0a9f8e48 SHA-1: 9ffc2f2243830a1f21e22d2e85f10dcc33c44c3a SHA-256: cab19b0bd63bc2bfea402165c13e1a27031ba9ebdb08b57439c23a80d80fdb91
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links, many pointing to disposable domains or compromised CMS upload storage, indicative of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and unreadable, but the presence of external URI heuristics and link farm indicators points to an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://hzqljsj.com/images/upload/File/41650812702.pdf In PDF document text
    • http://www.facyt.com.ar/ckfinder/userfiles/files/59444963895.pdfIn PDF document text
    • http://brandnewgoods.net/userfiles/file/93669945342.pdfIn PDF document text
    • https://abctranslink.com/ckfinder/userfiles/files/15656723583.pdfIn PDF document text
    • https://sportuna.be/ckfinder/userfiles/files/80451923363.pdfIn PDF document text
    • http://rockefellersgold.hu/editor_up/15682309886.pdfIn PDF document text
    • http://cesishotel.lv/res/wysiwyg/file/zimufanoli.pdfIn PDF document text
    • http://ityab.com/cache/fck_files/file/57734526384.pdfIn PDF document text
    • https://livresdarts.com/ckfinder/userfiles/files/sibemakalujelizor.pdfIn PDF document text
    • http://udokutscher.de/gfx/userfiles/files/ketalunodanoguvurerugu.pdfIn PDF document text
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/5a5a66cf1b8883433ae6d6d3b598f6ab/fogisut.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/16141077d9bd13---28771582706.pdfIn PDF document text
    • http://investbuild.ru/var/upload/file/tamobitebuguxef.pdfIn PDF document text
    • http://sun-green.de/ckfinder/userfiles/files/61318170662.pdfIn PDF document text
    • http://brno-skoleni.cz/ckfinder/userfiles/files/45684676114.pdfIn PDF document text
    • http://ajmason.com/admin/ckfinder/userfiles/files/27484700577.pdfIn PDF document text
    • http://birkhoffhi.com/userfiles/files/mumeremaku.pdfIn PDF document text
    • https://rrr71.ru/upload_picture/vetomalegodosokes.pdfIn PDF document text
    • http://podiummoda.ru/userfiles/file/6458891427.pdfIn PDF document text
    • https://fceresources.com/ckfinder/userfiles/files/nizolepij.pdfIn PDF document text
    • https://protradingindia.net/userfiles/file/bajimulovepatidejutiveke.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614268c404e09---22698516112.pdfIn PDF document text
    • https://reklama71.ru/upload_picture/kumimegukebuwafutaka.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=media+maker+free+downloadPDF 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_off0000e8e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8E0 17148 bytes
SHA-256: b0d88cf9778bcb98f3a573ff2f0198b6ceb30674dd58bf10a958c96ce4854f91
font_01_sfnt_off00011587.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11587 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012d9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D9E 10420 bytes
SHA-256: f6970ef9821cbdee92b952e0fd518596e8613a6f515e75dde67774aea9cbf496