Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c5161c7b4b167da…

MALICIOUS

PDF

65.5 KB Created: 2021-03-28 10:17:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 2398327851e23f2c83866e03b1c43ecf SHA-1: 2079e57b326748236b93856442400e4a0a34be45 SHA-256: 9c5161c7b4b167da1107fe75431a9ead24e3c07b11423b8188e80df36df3ee0b
184 Risk Score

Malware Insights

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

The PDF contains multiple embedded URLs, with at least one identified as a known malicious redirector. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body, though heavily obfuscated, appears to contain keywords related to the malicious URLs, suggesting a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://dafemum.ru/123?utm_term=petty+gangster+crossword+answer In PDF document text
    • https://cdn.sqhk.co/molodomo/iiejfjl/fejewimogevupaw.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4499329/normal_6038fd719815f.pdfIn PDF document text
    • http://xovumajinobog.iblogger.org/download_gratis_livros_espiritas.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4500186/normal_603d3282a3aa5.pdfIn PDF document text
    • https://cdn.sqhk.co/xeveweno/wrmiheM/business_dictionary_meaning_in_tamil_download.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4404730/normal_6002142c9b41e.pdfIn PDF document text
    • https://cdn.sqhk.co/xeduwukaxusa/hEigVhg/boteguledupalubopu.pdfIn PDF document text
    • https://cdn.sqhk.co/nodezaneripe/Hgebhh8/tufelawupow.pdfIn PDF document text
    • https://cdn.sqhk.co/dafibuxoki/dgdEtje/loop_recorder_implant_cpt_code_2020.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/ca6412c6-3658-414b-9584-57ebc33c3023/39299213657.pdfIn PDF document text
    • http://nowimirozox.atwebpages.com/sunbeam_heated_mattress_pad_-_queen_-_msu1gqs-n000-12c50.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c011d3a2-10bd-499d-9c44-7005b4dc5099/kindle_oasis_3_specs.pdfIn PDF document text
    • http://fotexamaluvim.epizy.com/odisha_road_map.pdfIn PDF document text
    • http://xufoziminep.onlinewebshop.net/88818523543.pdfIn PDF document text
    • http://jufofokisib.epizy.com/baby_shark_video_free_mp4.pdfIn PDF document text
    • http://letutemoxeluz.onlinewebshop.net/webidogipima.pdfIn PDF document text
    • http://xifeloj.onlinewebshop.net/buku_agama_islam_kelas_4.pdfIn PDF document text
    • https://s3.amazonaws.com/navoburarovada/attack_on_titan_movie_1_feuerroter_pfeil_und_bogen.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6b461ba0-7e21-4a8f-b3eb-b16457950a9f/myers_ap_psychology_textbook.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9a92ff55-2bcf-482f-ab44-6b32dc8a980b/83837861150.pdfIn PDF document text
    • https://s3.amazonaws.com/kugelilizibuwum/alt_codes_symbols.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_off0000c4f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4F0 5272 bytes
SHA-256: bd2a4e0dbd09676077a0bfe8247fb6dcda043a1f4db6fcd6a9d5e89c680b225f
font_01_sfnt_off0000d703.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD703 9864 bytes
SHA-256: a6c62a567fc833429d1056e0747f0d3b95312b7b06ee0e07c6f80d8088200822