Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9e2258e677db013…

MALICIOUS

PDF

79.2 KB Created: 2021-09-19 14:24:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4329c11f5f57b43f5baaba13ca5f6dd8 SHA-1: 2d001e6f0351af5829ddef9c8c800ee2d8308168 SHA-256: a9e2258e677db0132ea900b32789bf3ae129e6a2a4b79437e32ea7f3ab4a5481
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable domains hosting other PDFs. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO spam. The embedded JavaScript is a common technique for executing malicious code within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 6

  • 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.
  • 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 http://wskinbody.com/data/boardData/files/nipubasaxonoxikekix.pdf In PDF document text
    • http://goref.ru/files/file/pezudoge.pdfIn PDF document text
    • http://xn--80aaaaaikdebj9ccf1ayja1b5a3q.xn--p1ai/ckfinder/userfiles/files/57809480619.pdfIn PDF document text
    • http://cungcapbaoduongcuanhatban.com/upload/files/20862972426.pdfIn PDF document text
    • https://onecre.com/images/content/files/86021674525.pdfIn PDF document text
    • https://smshealthcareservices.com/ckfinder/userfiles/files/13189022594.pdfIn PDF document text
    • https://namratalakhotia.com/userfiles/files/jaresowixaxawomuwar.pdfIn PDF document text
    • http://struttur-arch.it/userfiles/files/17510160815.pdfIn PDF document text
    • http://bellina.pl/userfiles/file/59659600787.pdfIn PDF document text
    • https://rmduncanrealty.com/userfiles/files/27790332455.pdfIn PDF document text
    • http://bangiyaparishadtoronto.ca/bpt/editor/uploadfiles/berokusobivef.pdfIn PDF document text
    • http://hitplus.eu/userfiles/file/19220375527.pdfIn PDF document text
    • https://smgbid.com/ckfinder_userfiles/files/luvijikuk.pdfIn PDF document text
    • https://r4binsh4h9-att.com/contents/files/13347317247.pdfIn PDF document text
    • http://tipkeo.com/js/ckfinder/userfiles/files/63869197478.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fa64236925---62540850428.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/1613131920805f---69976692371.pdfIn PDF document text
    • https://101doctor.com/uploads/ckfiles/files/6139e318b2097.pdfIn PDF document text
    • https://www.mtiwelding.co.uk/admin/ckfinder/userfiles/files/kugem.pdfIn PDF document text
    • http://solee.cn/ckfinder/userfiles/files/16016621959.pdfIn PDF document text
    • http://nemdanangpho.com/uploads/2021-09-09/images/files/diner.pdfIn PDF document text
    • https://giraffeng.net/infodaily/gen-ckfinder/userfiles/files/lawupifuvenozalu.pdfIn PDF document text
    • https://srsatta.com/ckfinder/userfiles/files/92805223992.pdfIn PDF document text
    • http://realfootball.gr/userfiles/file/nozobimixeleza.pdfIn PDF document text
    • http://allycatering.com/userfiles/sepaxire.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=home+iptv+androidPDF 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_off0000d167.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD167 17424 bytes
SHA-256: 6638510634e8d831874bd077d0198fc1e9ffa36d64f9ca3d26825ec430bd0afa
font_01_sfnt_off0000feda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEDA 10396 bytes
SHA-256: e0bec9d0701ba07c144857f70f21134b7a75b215aaf66b719cb917343c8616de
font_02_sfnt_off00011645.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11645 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1