Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8848b8c36849435…

MALICIOUS

PDF

75.7 KB Created: 2021-09-19 20:29:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: c2b6281add1a0e9db896678a83bd8a96 SHA-1: 681ec53ab650c3a0bbdd34461281aa4e561309dc SHA-256: f8848b8c368494358459a978db24ac727905a9340dfc46ec44ac02c0b4c9b0e2
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the presence of numerous embedded URLs suggest a phishing or credential harvesting campaign. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://latgalesamatnieki.lv/files/file/pojezunojoxulewamewenabo.pdf In PDF document text
    • https://dreptultau.hotnews.md/upload/userfiles/files/kukolibetadiriwefu.pdfIn PDF document text
    • https://vico-inmobiliaria.com/ckfinder/userfiles/files/16994775747.pdfIn PDF document text
    • http://apexibd.com/uploads/fck_uploads/file/51559448416.pdfIn PDF document text
    • http://risme.vn/files/94415909406.pdfIn PDF document text
    • https://stradatextiles.com/upload/ckfinder/files/jetamapu.pdfIn PDF document text
    • http://cn-polylysine.com/d/files/49264886017.pdfIn PDF document text
    • https://www.gryf-wet.pl/ckfinder/userfiles/files/lisikevixomuga.pdfIn PDF document text
    • https://khangle.vn/uploads/images/files/44471774519.pdfIn PDF document text
    • http://milkyway-vn.com/upload/files/kapeliw.pdfIn PDF document text
    • http://bapassamarinda.id/assets/ckfinder/core/connector/php/uploads/files/79840355790.pdfIn PDF document text
    • https://hongming-eco.com/userfiles/file/guxoxij.pdfIn PDF document text
    • https://thegioidongphuc.net/ckfinder/userfiles/files/kinipuxizunamujalobakilix.pdfIn PDF document text
    • https://prolocolidodisavio.org/ckfinder/userfiles/files/xerasijofaloje.pdfIn PDF document text
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/7ba031c1bbf23cbf2ef67845d12acf93/87279966155.pdfIn PDF document text
    • https://coonvalleycc.com/userfiles/file/42058609094.pdfIn PDF document text
    • http://www.me.ntou.edu.tw/ckfinder/userfiles/files/20210917_181024.pdfIn PDF document text
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/f473216394508055667f8a7945ecb93b/92146116740.pdfIn PDF document text
    • https://expobar.vn/app/webroot/files/images/pages/files/lakovizaduvujajesorib.pdfIn PDF document text
    • https://bloomland.com/sites/bloomland.com/files/zofora.pdfIn PDF document text
    • https://pakianco.ir/data/image/uploads/news/files/59685846180.pdfIn PDF document text
    • http://klimatyzacjaradom.pl/userfiles/file/69105327383.pdfIn PDF document text
    • http://otczenacts.com/media/files/91133038215.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=zenui+dialler+appPDF 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_off0000c408.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC408 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dc1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC1A 18156 bytes
SHA-256: f5934d488982782d2bf18c076cac33fc1d0a86f0ef588783496d23ab4887e1e7
font_02_sfnt_off00010b43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B43 10064 bytes
SHA-256: 37a886c485680f03479da615cfa4c31f9334d4eeefb1219d732fcd7c5757f1d3