Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f853e8cdbc7827b…

MALICIOUS

PDF

70.0 KB Created: 2021-09-30 10:06:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: a8e3b20d1a061847cab26d84e44a32ce SHA-1: c4f5e9ce444267c52932135bb2e05fa9cb03e09a SHA-256: 8f853e8cdbc7827b755ce8178e3e7cbf3f81284f00a49652a8d0e1b78fd735f4
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for delivering malicious content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the PDF is designed to redirect users to a large number of distinct hosts, likely for phishing or malware distribution. The ML classifier and ClamAV detection strongly support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://karjerastests.bankai.lv/ckfinder/userfiles/files/80776643428.pdf In PDF document text
    • http://7m-shop.com/userfiles/file/rewojopewutolimabel.pdfIn PDF document text
    • https://vidaleve.ind.br/ckfinder/userfiles/files/wirixeda.pdfIn PDF document text
    • https://virtualpulse.eu/UserFiles/file/giretikazuvabuvatulogori.pdfIn PDF document text
    • http://lollanaclinic.com/image/upload/File/88823842067.pdfIn PDF document text
    • https://www.stnedu.com/ckfinder/upload/files/lunipotimi.pdfIn PDF document text
    • http://nzozkrowodrza.pl/uploads/editor/file/dejonipu.pdfIn PDF document text
    • https://njshore.drinkpoint.com/uploads/files/2173643886.pdfIn PDF document text
    • http://darangyi.com/userData/board/file/nokexutugewejularamitev.pdfIn PDF document text
    • https://vnmmalta.com/userfiles/file/gidebexa.pdfIn PDF document text
    • http://anabakorea.jp/userfiles/file/fukigibofiz.pdfIn PDF document text
    • https://quatden.vn/webroot/img/files/fawedazel.pdfIn PDF document text
    • https://padservhosting.com/userfiles/file/42602432464.pdfIn PDF document text
    • http://npk-bypassdrr2.com/file_media/file_image/file/93122718599.pdfIn PDF document text
    • http://www.coverseg.com/uploads/ckfinder/files/vamunuvu.pdfIn PDF document text
    • http://speed-r.com/js/upload/files/bidogug.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/2i45qvtffum066j28j4i9b1b67/32963230452.pdfIn PDF document text
    • https://kompaspt1.com/contents/files/80008690791.pdfIn PDF document text
    • http://abwjefferson.com/uploads/files/30214041171.pdfIn PDF document text
    • http://xmzhj.com/UserFiles/file/tunekiwa.pdfIn PDF document text
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/967fa5ac5e6af7e253bb4d0d19352f95/24424251574.pdfIn PDF document text
    • https://ghnservizi.com/file/laperuliwupokede.pdfIn PDF document text
    • http://zamgph.com/FCKeditor/editor/filemanager/connectors/php/uploads/file/070450116334.pdfIn PDF document text
    • https://unosms.us/userfiles/file/97874781491.pdfIn PDF document text
    • https://bangprice.com/bangprice.com/beta/cms_image/file/farigemilatopeni.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=android+to+apple+tv+mirroringPDF 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_off0000b0fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0FA 10616 bytes
SHA-256: d1850c0563adac1817213ea29f3063ecb6c44a32fd83eb16e1d328c9ea9db177
font_01_sfnt_off0000c8fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e10c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE10C 16236 bytes
SHA-256: f4004b70b0be9a953e26974a14e746dd61b483f66cb21a20003f140d11ecb428