Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf5b91fb12745a17…

MALICIOUS

PDF

83.4 KB Created: 2021-04-01 02:07:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 7cdbdce91b95ad85fb4bedb8e61aea98 SHA-1: dedfc3704ae734f52e95a430a87161bd56f11d8d SHA-256: bf5b91fb12745a17183de8af59a5af140537e861b3c8ebc45a91f883060a9b0c
136 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, specifically identified as a phishing trojan. It contains an embedded URI and a high-risk heuristic indicating an image lure linking to an SEO redirector, specifically `https://bologen.ru/strik?utm_term=why+isn%2527t+my+pressure+cooker+lid+locking`. The document body, though heavily obfuscated, contains text related to pressure cookers and the wkhtmltopdf application, suggesting a lure to disguise the malicious link.

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
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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/strik?utm_term=why+isn%2527t+my+pressure+cooker+lid+locking PDF link annotation
    • https://cdn.sqhk.co/gijesali/q6giuib/830137777.pdfIn PDF document text
    • http://dabopoxele.getenjoyment.net/7699102925.pdfIn PDF document text
    • http://zeruxejobimal.mywebcommunity.org/alok_ranjan_dasgupta_kobita_download.pdfIn PDF document text
    • https://cdn.sqhk.co/kixobaza/Xhbkcfz/redfin_seattle_jobs.pdfIn PDF document text
    • http://rirelavemug.iblogger.org/pufuludowalujabetixavinar.pdfIn PDF document text
    • http://desajegurake.scienceontheweb.net/15853941003.pdfIn PDF document text
    • https://cdn.sqhk.co/vadavenaw/UwqTjhj/drone_fancy_dress.pdfIn PDF document text
    • https://cdn.sqhk.co/ragebobeb/3dlgdhv/44642198083.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://wojudor.epizy.com/xtreme_vapor_barrier_data_sheet.pdfIn PDF document text
    • https://s3.amazonaws.com/subopukomanaw/westlife_fool_again_instrumental.pdfIn PDF document text
    • https://s3.amazonaws.com/nafamaragisek/keto_cookbook_amazon.ca.pdfIn PDF document text
    • https://s3.amazonaws.com/tasufagijaremo/bangla_audio_song_2018_free.pdfIn PDF document text
    • https://s3.amazonaws.com/fefurorobumi/71512979964.pdfIn PDF document text
    • https://s3.amazonaws.com/dejazuvorira/forest_exam_answer_key_2018.pdfIn PDF document text
    • http://morikid.epizy.com/fitavo.pdfIn PDF document text
    • https://s3.amazonaws.com/wutogugej/capitulation_surrender.pdfIn PDF document text
    • https://s3.amazonaws.com/kufazete/2018_calendar_uk_free.pdfIn PDF document text
    • http://xivubijorudi.epizy.com/why_is_my_dryer_not_drying_clothes_well.pdfIn PDF document text
    • http://xavuguwibimovin.epizy.com/autodesk_revit_architecture_for_mac_free.pdfIn PDF document text
    • http://rodisasedozax.myartsonline.com/miguel_de_cervantes_el_quijote.pdfIn PDF document text
    • http://wobanunep.myartsonline.com/wendys_company_nutrition_information.pdfIn PDF document text
    • https://s3.amazonaws.com/fukezavazuj/gulix.pdfIn PDF document text
    • https://s3.amazonaws.com/gorajikunobixi/year_5_measure_and_calculate_the_perimeter_of_composite_rectilinear_shapes_in_centimetres_and_metres.pdfIn PDF document text
    • https://s3.amazonaws.com/lunojol/budetalunaru.pdfIn PDF document text
    • https://s3.amazonaws.com/fewifuwu/cisco_networking_academy_exam_answers_chapter_5.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_off000107a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107A1 5492 bytes
SHA-256: 83d59a20139636c15aff4051c6c74a288d61e06a38327265f49c103ab9921fd8
font_01_sfnt_off00011a43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A43 11020 bytes
SHA-256: c1530a5c469abe20cdc6a003d83046580ae60c27aa001d5daffc13e5b26ca17b