Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc205a21661c1118…

MALICIOUS

PDF

75.1 KB Created: 2021-03-22 21:17:39 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: f72af509115da35b58fc248ef84558b7 SHA-1: adca4ff858c9bb58d6c11b31fd3f97e0bbea12bd SHA-256: dc205a21661c11182e623bffe39dfb3a1405b7f966936bd36e7332e22dd3d409
126 Risk Score

Malware Insights

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

The file is a PDF that contains numerous embedded URLs, many of which point to disposable domains and are flagged as part of a link farm. The ClamAV detection and ML classifier strongly indicate malicious intent, specifically identified as a phishing trojan. The document body, though heavily obfuscated, contains references to 'atomic structure practice quiz answers' and 'wkhtmltopdf', suggesting a lure to a malicious site.

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://bologen.ru/wix?keyword=atomic+structure+practice+quiz+answers PDF link annotation
    • http://mugedly.xyz/day_to_day_english_conversation_sentences_in_officebvy5g.pdfIn PDF document text
    • http://lovumodezubudem.iblogger.org/liminal_thinking_wiki.pdfIn PDF document text
    • https://cdn.sqhk.co/vafodagusun/LgdIgje/40815919627.pdfIn PDF document text
    • http://erogan-encolumbia.site/household_expenses_spreadsheet_australiatdtcx.pdfIn PDF document text
    • https://cdn.sqhk.co/wibetaxor/iTighax/lenovo_laptops_for_sale_in_kenya.pdfIn PDF document text
    • http://goldstein.berlin/33344759245f0gy3.pdfIn PDF document text
    • https://rozonamofo.weebly.com/uploads/1/3/4/7/134751518/vosedazovepabu.pdfIn PDF document text
    • https://cdn.sqhk.co/pikuworano/hdS19e2/telafofedililamakuxupup.pdfIn PDF document text
    • https://cdn.sqhk.co/gegatuzikat/ihoANhd/jolly_phonics_flashcards_printable.pdfIn PDF document text
    • http://bachanalytics.com/exercices_corrigs_sur_les_acides_alpha_aminspsui2.pdfIn PDF document text
    • https://pazowega.weebly.com/uploads/1/3/2/3/132303248/381d1.pdfIn PDF document text
    • https://cdn.sqhk.co/faroziwe/ichbhgP/35952022394.pdfIn PDF document text
    • http://reduslim-eu.site/piwigop5dpo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/500a711d-26f9-4846-b6aa-9d0f8d4f3e0f/delta_scroll_saw_replacement_parts.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/498e82ab-168d-4059-a902-362cbb01a703/vutawazigisiv.pdfIn PDF document text
    • http://xitufadaxavak.epizy.com/nemomisezug.pdfIn PDF document text
    • https://d89a15f7-21b5-45f0-b9b4-bc5b7be68842.filesusr.com/ugd/18e821_f829347c2cb146668a588dd1209bf006.pdf?index=trueIn PDF document text
    • https://7fad2989-91b8-457c-89bc-9a0e7aeef19f.filesusr.com/ugd/b03ff3_cec8912350cf4bb99b87ca969a5c9c04.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/92b450db-e9f0-4594-ae04-b81513f1e217/hp_officejet_6500a_plus_web_service.pdfIn PDF document text
    • http://pususarejopo.epizy.com/kikureped.pdfIn PDF document text
    • http://lagorov.rf.gd/35737473265.pdfIn PDF document text
    • http://zetesapoxus.epizy.com/11284552879.pdfIn PDF document text
    • https://ebc1add8-0b9d-418e-9e4a-1e287827e933.filesusr.com/ugd/ab63e3_62c8005aa7a64940ac5ac4da7b99d5da.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/33c86820-8607-44ab-8435-25d7d8c918a2/mediasonic_probox_hf2-su3s2_manual.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_off0000e5e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5E8 5304 bytes
SHA-256: 627515b6d6ee1da0f7fa1503fcc3c64ee654f140d33f7dd6cdec80f1523fb119
font_01_sfnt_off0000f7fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7FB 11484 bytes
SHA-256: 68a3e0a2a1b3c9a840310812149224e3aee1c9f7757d260a7ecd2aa1392bba2c