Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc7d068f50a70bdd…

MALICIOUS

PDF

79.2 KB Created: 2021-03-18 16:57:03 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: 540523ea27f30a73288e1c2fb68e7985 SHA-1: 43d47fa92b12cf4dcd468fabf1189868525c1bd2 SHA-256: dc7d068f50a70bdd432f74867384e2daafa2e1165450f1ce341e2ccc38270a19
126 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many pointing to disposable domains, suggesting a phishing or spam campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body, though heavily obfuscated, contains references to academic topics and the wkhtmltopdf application, likely serving as a lure to disguise the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://pelibifir.ru/award?keyword=neurosis+and+psychosis+freud+pdf PDF link annotation
    • http://nebofimanigi.sportsontheweb.net/how_do_i_fix_the_pick_motor_stalled_on_my_hp_8600.pdfIn PDF document text
    • http://femetorisufi.sportsontheweb.net/base64_decode_file_php.pdfIn PDF document text
    • http://matawobedopikam.mywebcommunity.org/wolawewadutite.pdfIn PDF document text
    • http://kujamemapevubu.mypressonline.com/multivariate_linear_regression_python_sklearn.pdfIn PDF document text
    • http://manuximaxemeje.scienceontheweb.net/which_smart_thermostats_do_not_require_a_c_wire.pdfIn PDF document text
    • http://pewadulojuba.mypressonline.com/interview_questions_for_project_manager_uk.pdfIn PDF document text
    • http://tuvosudokalidu.scienceontheweb.net/judasigugukikidi.pdfIn PDF document text
    • http://zobotalemogi.sportsontheweb.net/relion_confirm_meter_manual.pdfIn PDF document text
    • http://mukinumatonewo.getenjoyment.net/what_is_critical_thinking_in_high_school.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/b649802b-8d65-4351-a469-08f2297235f3/lezajadobobodevupul.pdfIn PDF document text
    • http://nununad.myartsonline.com/77496631343.pdfIn PDF document text
    • https://1628ddcf-e301-416d-9649-d9339b85441b.filesusr.com/ugd/0b1079_194222657293477b931e849ee8baed12.pdf?index=trueIn PDF document text
    • http://desovizipelo.onlinewebshop.net/zogegadinufok.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b7526447-9937-4215-a492-77778ce33054/star_trek_discovery_episode_8_season_3.pdfIn PDF document text
    • https://s3.amazonaws.com/xapota/korojetujetixotubariwoza.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/17511467-9a29-4c94-87c6-9d31ff30aad7/jimutexafub.pdfIn PDF document text
    • https://780c8f77-0f51-49ab-8dd1-60a90eb210a4.filesusr.com/ugd/1b8612_dd8a5948b0514b3b93494d73effee17b.pdf?index=trueIn PDF document text
    • https://557345b1-98c6-442d-b460-9e357c178e5b.filesusr.com/ugd/dfb5f8_c47016b7e9b843ccb00a80012dbc5ead.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/cd86c478-67c1-4f8f-8bc2-536e88c25d48/big_blue_party_speaker_troubleshooting.pdfIn PDF document text
    • https://s3.amazonaws.com/resixexi/daxisosu.pdfIn PDF document text
    • http://gozidonozali.myartsonline.com/zepuku.pdfIn PDF document text
    • https://s3.amazonaws.com/vudivuzakal/bativowil.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/698904df-1b54-4afc-a2ee-04a485883b71/new_stephen_king_movies_2019.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_off0000f43f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF43F 5280 bytes
SHA-256: f37f9460686f1b37afd0bbefa499315379a5ffc800b55a2286fb272dffd63369
font_01_sfnt_off0001063f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1063F 12424 bytes
SHA-256: da475cf9cf386ad90e27c1ebd8137a8c55a321c7e56bb3669dcb7382d045c30d