Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4f191bfbf1f30b3…

MALICIOUS

PDF

70.2 KB Created: 2021-09-28 04:49:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 061f19507952b81c1faa1555eb1ccc9a SHA-1: 2a2b1dc5d2a20c385f79d605f3e5a5f3f5acf047 SHA-256: d4f191bfbf1f30b3f4c6db5f076c020a515e504a754303210092db6b8903528f
134 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier with high confidence. It contains embedded JavaScript and numerous external URIs, including one pointing to 'nomylo.ru' which is associated with password-related search terms, suggesting a phishing lure. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates the document is designed to host many links on disposable domains, further supporting a malicious intent to redirect users to potentially harmful sites.

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://nomylo.ru/uplcv?utm_term=how+to+see+saved+network+password+android PDF link annotation
    • http://fotografoenricogiampieri.it/userfiles/files/xojerezuge.pdfIn PDF document text
    • https://tiklatakip.com/calisma2/files/uploads/64108131693.pdfIn PDF document text
    • http://globalone-mould.com/gbw/fckfiles/20210903180334.pdfIn PDF document text
    • https://solucionaesp.com/ckfinder/userfiles/files/jomakewewogulopame.pdfIn PDF document text
    • https://riminabda.sk/userfiles/file/kukaranuzutogerawinu.pdfIn PDF document text
    • http://elitaliaweb.it/upload/file/38839269780.pdfIn PDF document text
    • http://quimis.org/js/ckfinder/userfiles/files/7592366830.pdfIn PDF document text
    • http://erainbowrealty.com/userfiles/file/22914784473.pdfIn PDF document text
    • http://ufcnagykanizsa.hu/userfiles/file/tesusaxinusakifurewatida.pdfIn PDF document text
    • http://gfk-schwimmbad.de/i/File/18304434607.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f4ad6c6721---jimakewifatexezorer.pdfIn PDF document text
    • http://king-tableware.com/uploads/files/202109070215579272.pdfIn PDF document text
    • http://loca-granderoue-montaletang.com/ckfinder/userfiles/files/32128089605.pdfIn PDF document text
    • https://ladangmimpi.com/contents/files/jorosozokimilimoguzowas.pdfIn PDF document text
    • http://solarexperten.ch/fckeditor/editor/images/file/xezadumomexatalujaf.pdfIn PDF document text
    • http://skinct.com/upload_file/file/Fl202109180952518349.pdfIn PDF document text
    • http://albino-pitti.com/pub_img/file/kakel.pdfIn PDF document text
    • http://cgpharma.in/cote_dor_import/admin/ckfinder/userfiles/files/xevewojutavevuvigek.pdfIn PDF document text
    • http://phoiinnhiet.com/images/uploads/files/85748488794.pdfIn PDF document text
    • https://sportuna.be/ckfinder/userfiles/files/fikilat.pdfIn PDF document text
    • http://xn--9w3b270a7kf.kr/data/editor/file/wazobum.pdfIn PDF document text
    • https://tatvan.in/userfiles/file/41005073956.pdfIn PDF document text
    • http://www.europesolidaire.eu/userfiles/files/76375528042.pdfIn PDF document text
    • https://www.colegiodomus.com.br/js/ckfinder/userfiles/files/44662315917.pdfIn PDF document text
    • http://sangjeom.com/userfiles/file///situnikoxifizojajepij.pdfIn PDF document text
    • 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_off0000b199.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB199 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c9b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9B0 10576 bytes
SHA-256: e3a11ab22e734ff6ce7d7e20589a98a9234aea400cecc4d52d1acdfcc303ee75
font_02_sfnt_off0000e1f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1F7 16024 bytes
SHA-256: a4d522dd659060d985bfe4fb1aba447131d052142e9d25ef2113f20741613da3