Malicious PDF — malware analysis report

Static analysis result for SHA-256 98622b83f826fe99…

MALICIOUS

PDF

92.1 KB Created: 2021-09-12 16:03:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 160ef8e0c3e1f2092e09498e0ec9e285 SHA-1: 67c2c7e32d6ec954a02d6222b8826f5cdddfc5f0 SHA-256: 98622b83f826fe9984f14d799adb57e6372df33fc3e97dc8c306cbf067a69662
126 Risk Score

Malware Insights

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

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous external URIs, with a significant heuristic firing identifying it as a link farm on disposable hosting, suggesting a phishing or spam distribution tactic. No scripts were extracted, and the document body was unreadable, but the overall structure and heuristic firings point to a campaign distributing malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

Heuristics 5

  • 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.
  • 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.fuchingrading.com/upload/file/jemejugetetevivufadudubek.pdf In PDF document text
    • http://epilia.com/upload/FCKEditorfile/gisemufosas.pdfIn PDF document text
    • http://philipwillettelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/lobimefiripolakagutiwa.pdfIn PDF document text
    • http://uzks.hr/upload/datoteke/mimov.pdfIn PDF document text
    • https://thefencedocumentary.com/adminfiles/file/tatudan.pdfIn PDF document text
    • http://digilit.ir/basefile/digilitir/files/97433244765.pdfIn PDF document text
    • http://phuketdriveschool.com/userfiles/file/5205379776.pdfIn PDF document text
    • http://propertiesforrent.com/userfiles/file///jikorelijirofizetavun.pdfIn PDF document text
    • https://vcvscr.cz/www/www/fckphotos/file/32753670053.pdfIn PDF document text
    • http://owv-sad.de/userfiles/files/moziteketijenisowidesimu.pdfIn PDF document text
    • http://tmkb.org.tr/ckfinder/userfiles/files/29820447516.pdfIn PDF document text
    • http://moto-bike.pl/userfiles/file/64102795868.pdfIn PDF document text
    • http://donleroy.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/18379538703.pdfIn PDF document text
    • https://alice-immo.com/userfiles/file/79621559386.pdfIn PDF document text
    • https://lanna-flyingclub.com/ckfinder/userfiles/files/zofawe.pdfIn PDF document text
    • https://alhasooncorp.com/Files/files/jiretadanumula.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/15762556689.pdfIn PDF document text
    • https://sayurhijau.com/contents/files/14535431804.pdfIn PDF document text
    • http://kmkonsult.cz/userfiles/file/70591010837.pdfIn PDF document text
    • https://creativenursery.net/home/creative/public_html/ckfinder/userfiles/files/1676437216.pdfIn PDF document text
    • http://bilateralmatters.org/userfiles/file/12492003501.pdfIn PDF document text
    • http://vervesimuhub.com/userfiles/file/82910892365.pdfIn PDF document text
    • http://srihemkuntschoolint.com/slbdavbatala/userfiles/file/88261599804.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=bolane+wala+ringtonePDF 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_off0000fe81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE81 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011693.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11693 20276 bytes
SHA-256: 5ed53c38be88f5e38e769e370ab54bb465a91357142f125b8b4fccfa66a97340
font_02_sfnt_off00014bb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14BB3 10252 bytes
SHA-256: c056bba27a43cd7cd16d63d4fb3e36f3d256ed19661af90df1a5eccefc669b2a