Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca112343fcac88f9…

MALICIOUS

PDF

104.3 KB Created: 2021-04-08 02:53:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 124540bbb1af463c2add1677409b145e SHA-1: c37f0612853628e117600fda869f442f079d1e87 SHA-256: ca112343fcac88f905da14c50dc085f19cf788bc3bffb6260fd76b2cc4623423
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The sample is a PDF document flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier with high confidence. Heuristics indicate it functions as a link farm and employs a social-engineering lure to trick users into installing a browser extension or update. While no scripts were directly extracted, the presence of external URIs and the nature of the lure suggest a potential for JavaScript execution or exploitation to deliver a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://leonvi.ru/123?utm_term=agri+alert+128+manual PDF link annotation
    • http://in-step.shop/gomirexefeveresm0gb7.pdfIn PDF document text
    • https://cdn.sqhk.co/zopizote/jegiuxa/scary_island_dream_codes_acnh.pdfIn PDF document text
    • https://cdn.sqhk.co/fesakesovoka/ghgihay/lessons_english_grammar.pdfIn PDF document text
    • http://vedatolinofiz.iblogger.org/sonumivijir.pdfIn PDF document text
    • https://cdn.sqhk.co/zikegasenar/9vWihvw/world_war_brothers_ww2_mod_apk.pdfIn PDF document text
    • https://cdn.sqhk.co/gulofiji/hgbhhic/sumif_contains_text_google_sheets.pdfIn PDF document text
    • http://buyervannakupitvsem.xyz/freightliner_cascadia_2017_manual8t2v9.pdfIn PDF document text
    • https://cdn.sqhk.co/sogunixe/Gjaggee/bagomazavaza.pdfIn PDF document text
    • https://cdn.sqhk.co/juwafajem/jhigirp/botolujarugunamorosariwu.pdfIn PDF document text
    • https://cdn.sqhk.co/vanewano/a0Uhghh/54289137772.pdfIn PDF document text
    • http://poludafe.iblogger.org/widenadu.pdfIn PDF document text
    • https://cdn.sqhk.co/rupizabiweze/aijNieb/chicken_invaders_3_xmas_download.pdfIn PDF document text
    • http://kokilubowo.22web.org/96159599815.pdfIn PDF document text
    • https://cdn.sqhk.co/dodalowogiv/3ghq0jh/dog_baby_yoda_meme.pdfIn PDF document text
    • https://cdn.sqhk.co/mixaluwekitu/jikJghG/xupevapod.pdfIn PDF document text
    • https://cdn.sqhk.co/wunasesev/jdFjegi/15335081467.pdfIn PDF document text
    • https://cdn.sqhk.co/moturalogupe/jagh9ih/republique_restaurant_la_brea_los_angeles.pdfIn PDF document text
    • https://cdn.sqhk.co/favosejo/ASBwmgj/stickers_maker_para_whatsapp.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://guxajez.rf.gd/best_book_to_learn_html_and_css_for_beginners.pdfIn PDF document text
    • http://nujipuluz.epizy.com/steel_weight_conversion_table.pdfIn PDF document text
    • http://fidazel.epizy.com/71883116725.pdfIn PDF document text
    • http://zoxuleresuxenez.rf.gd/89984266493.pdfIn PDF document text
    • http://dofumuligo.rf.gd/esc_guidelines_myocardial_infarction_2012.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://scripts.sil.org/OFLIn 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_off0001431e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1431E 5196 bytes
SHA-256: fe185922c9aa5aff33ecf089d1d6bb67d0755d77caf1ed4a7753c7a1b6a75bbf
font_01_sfnt_off000154ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x154BA 12236 bytes
SHA-256: e6e5511dd7805439e41eac0e154cb71e41fa2be18e2fd6d97f05f86fb07fb72f
font_02_sfnt_off00017e57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17E57 16060 bytes
SHA-256: 1143ecdd1036854af7781a9416d0a82fe6fe24e09269eea81b933035be45ec4a