Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef25724c6b92e937…

MALICIOUS

PDF

75.5 KB Created: 2021-03-04 03:17:47 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: 2aa4afe3077f3845765b29ca3279bc1f SHA-1: 865bc8ac81c170caf0ec205c8289eb7429a42872 SHA-256: ef25724c6b92e937ee5f880155997848355e831b744816d73aae942f73758677
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. It contains numerous external URIs, with a primary suspicious URL being https://mezovuduw.ru/wix?keyword=ap+calculus+ab+exam+study+guide. The document body, though partially corrupted, suggests a lure related to an 'Ap calculus ab exam study guide'. The presence of embedded URLs and the overall structure point towards a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://mezovuduw.ru/wix?keyword=ap+calculus+ab+exam+study+guide PDF link annotation
    • http://lapitubemexidi.mywebcommunity.org/haier_portable_washer_drain_hose.pdfIn PDF document text
    • http://paselon.getenjoyment.net/sisap.pdfIn PDF document text
    • http://salizurewaki.mypressonline.com/27967561715.pdfIn PDF document text
    • http://weviwoza.22web.org/timex_wr50m_set_date.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://luxusuriva.epizy.com/ozymandias_why_is_it_ironic_that_the_statue_has_crumbled.pdfIn PDF document text
    • http://xavobuwog.epizy.com/46214490967.pdfIn PDF document text
    • http://nabenejajoko.myartsonline.com/8918707493.pdfIn PDF document text
    • http://zaxenedapepobu.rf.gd/how_to_clean_hoover_max_extract_carpet_cleaner.pdfIn PDF document text
    • http://wurasegato.rf.gd/self_certification_form_template.pdfIn PDF document text
    • http://lujuxepaxizi.rf.gd/bose_cinemate_gs_series_2_bluetooth.pdfIn PDF document text
    • http://degedudu.rf.gd/jeberoxozuwabefovijuxuba.pdfIn PDF document text
    • http://voxinuxo.epizy.com/dotolixadawejegosone.pdfIn PDF document text
    • http://rufevobovejexe.rf.gd/10017222668.pdfIn PDF document text
    • http://kikodanaso.epizy.com/nada_carmen_laforet_english.pdfIn PDF document text
    • http://zafediluxewo.rf.gd/final_cut_pro_x_trial_crack_mac_el_capitan.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e920.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE920 5596 bytes
SHA-256: 4069693aa51f63ad369a657a4ed598d3558bdb6849d734e07c3a7b3cc12583a9
font_01_sfnt_off0000fc23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC23 10764 bytes
SHA-256: 1927b97729648878d96ff2847daa7303178f29c9c7ab7584f1f6318063b8132a