Malicious PDF — malware analysis report

Static analysis result for SHA-256 798b90a2283ed166…

MALICIOUS

PDF

74.4 KB Created: 2021-04-10 09:07:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 0d310da0196ef0dc3cda4f8a73837883 SHA-1: 1b8fefe2f1bf444c46122ed7c68a52bdeb6e24bf SHA-256: 798b90a2283ed166f4e2280548f1eb4c448ec3659873de7d042a5b2c9c32d7c5
126 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. It contains numerous external URIs, including one that appears to be a redirector with UTM parameters, suggesting a phishing or malware distribution attempt. The document body is heavily obfuscated, but the presence of external links and the overall heuristic firings point towards a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://nipisod.ru/strik?utm_term=blackbird+beatles+tab+lyrics PDF link annotation
    • http://spencermcman.us/vinojifuxe77yrz.pdfIn PDF document text
    • http://cetakchantek.com/samsung_galaxy_tab_a_t290_review76zy3.pdfIn PDF document text
    • http://rusidaf.22web.org/calefon_solar_inta.pdfIn PDF document text
    • http://winsbig.space/xoveridedaxiduvijetuzujone3f.pdfIn PDF document text
    • http://rodina38.ru/15977142065jllhg.pdfIn PDF document text
    • http://pressit.space/the_circulatory_system_worksheet_answers_keyefejc.pdfIn PDF document text
    • https://nogexumojadug.weebly.com/uploads/1/3/4/2/134235638/5497839.pdfIn PDF document text
    • https://kuzapulekoxiror.weebly.com/uploads/1/3/2/6/132681507/5829486.pdfIn PDF document text
    • http://austritkfa.com/rajini_murugan_chella_kutty_song_free_downloadgblw2.pdfIn PDF document text
    • http://prolac.ru/545564482689ad7f.pdfIn PDF document text
    • http://jafedaroz.iblogger.org/wahls_protocol_diet_plan.pdfIn PDF document text
    • https://filafibiwi.weebly.com/uploads/1/3/4/3/134316544/samozev_timul.pdfIn PDF document text
    • https://pojikajuruwasi.weebly.com/uploads/1/3/2/6/132695468/zesoxozoso.pdfIn PDF document text
    • https://wefuguveriviwex.weebly.com/uploads/1/3/4/8/134873390/e22486de5e.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/xelimewat/singer_quantum_stylist_9960_problems.pdfIn PDF document text
    • https://s3.amazonaws.com/bogeguva/33430708806.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/561ace58-191c-4d26-80e3-ce067f2b2188/before_anna_todd_chapters.pdfIn PDF document text
    • http://rorodev.rf.gd/power_of_speaking_in_tongues.pdfIn PDF document text
    • http://sasajido.epizy.com/pdf_file_combiner_software.pdfIn PDF document text
    • https://s3.amazonaws.com/vitelitubovuluj/falifosolu.pdfIn PDF document text
    • https://s3.amazonaws.com/wefadep/what_is_the_meaning_of_the_movie_a_river_runs_through_it.pdfIn PDF document text
    • http://mabofikoparu.epizy.com/sontag_against_interpretation_criticism.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2706ff5e-aa04-4e47-a083-e3567077061e/vexujigifofudanal.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_off0000e631.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE631 5288 bytes
SHA-256: eb45063a8b87b76133d7bf650247263591e67a37340951d3b22f0de93e63baa4
font_01_sfnt_off0000f83d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF83D 10628 bytes
SHA-256: 4e1e162de22e61fbc2a17a2f024d091dfd3945a30411732dbdfe073be8d6adec