Malicious PDF — malware analysis report

Static analysis result for SHA-256 0db800aa7db5ed3e…

MALICIOUS

PDF

73.5 KB Created: 2021-05-10 02:50:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: ef9b25ce122442cbd9147c5165d58351 SHA-1: d2cc43fdb13bdda1be0e7e1178509117b83d1dd5 SHA-256: 0db800aa7db5ed3eef189bd817e0ccc9b618d5b42ede0d9e77372e1bccb20e56
126 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to disposable domains, and is flagged by ML classifiers and ClamAV as malicious. The document body, though heavily obfuscated, suggests a lure related to educational materials, specifically a 'quadratic equation practice worksheet'. The presence of external URIs and the link farm heuristic indicate an attempt to redirect the user to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • 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.
  • 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://vilenefex.ru/strik?utm_term=quadratic+equation+practice+worksheet+with+answers PDF link annotation
    • https://s3.amazonaws.com/vovuzize/raboferope.pdfIn PDF document text
    • http://bhd-management.space/tesasivodevujewavavesifxkos.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4499942/normal_60633ba3eda50.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385427/normal_6012c2b5a128f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4391327/normal_5feff3049c3d5.pdfIn PDF document text
    • http://gitikirazidapi.medianewsonline.com/calculus_early_transcendentals_2nd_edition_solutions_manual.pdfIn PDF document text
    • http://seamanygau.best/download_twilight_full_movie_in_hindi_dubbedcuzbs.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4416935/normal_6008e23999e47.pdfIn PDF document text
    • http://laribij.scienceontheweb.net/defending_jacob_novel_by_william_landay_ending.pdfIn PDF document text
    • http://bilkaita.space/657585604778n9nh.pdfIn PDF document text
    • http://leftoutclub.com/61983517558novqg.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4467586/normal_5fefb21a3f372.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4391326/normal_601816b972af6.pdfIn PDF document text
    • https://s3.amazonaws.com/zupenafud/sefamojotusapepuluzimumak.pdfIn PDF document text
    • http://dugules.iblogger.org/pancreatic_anatomy.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4464052/normal_5ff7a4201f7e6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367302/normal_5fd935b5a73d8.pdfIn PDF document text
    • https://s3.amazonaws.com/bulikowexunepov/pandaria_flying_trainer.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4425915/normal_606593d8b5056.pdfIn PDF document text
    • https://s3.amazonaws.com/defujo/canon_xh_a1_video_outputs.pdfIn PDF document text
    • http://tryraisins.club/petezodi9ite.pdfIn PDF document text
    • http://www.ascendercorp.com/In extracted file (font_00_sfnt_off0000df2b.bin)
    • http://www.ascendercorp.com/typedesigners.htmlIn extracted file (font_00_sfnt_off0000df2b.bin)
    • http://radoneg.rf.gd/iron_mike_pitching_machine_instruction_manual.pdfIn PDF document text
    • http://bufijonewufo.onlinewebshop.net/41911551526.pdfIn PDF document text
    • http://tanasebebibe.epizy.com/zuzagurix.pdfIn PDF document text
    • http://gosaduzunake.myartsonline.com/how_to_stretch_for_plantar_fasciitis.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 extracted file (font_00_sfnt_off0000df2b.bin)

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF2B 5472 bytes
SHA-256: 312602788bd85a6009179d72d5a5bc4c9b707121d107daa598ceb4dceca905f1
font_01_sfnt_off0000f1d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1D1 11108 bytes
SHA-256: 1fdd2ee339fcb6c6184087bddde5695777de40c964088ac048596c3b7d96fd25