Malicious PDF — malware analysis report

Static analysis result for SHA-256 81d4b39fe25f22e9…

MALICIOUS

PDF

81.3 KB Created: 2021-03-09 05:06:45 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 03a2ee6cd34dbb7026d7103e074441f8 SHA-1: ccf255e6832ba2c288ad469c605b415251edab9f SHA-256: 81d4b39fe25f22e9331176422d77ad021525d4b7aa36276c2c78d09f2effc084
136 Risk Score

Malware Insights

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

The PDF file uses an image lure to disguise a link to an SEO redirector, masquerading as a free download for 'christmas carols sheet music for piano'. This technique is commonly used for phishing or to deliver malware. The ML classifier and ClamAV detection strongly indicate malicious intent, and the embedded URL points to a suspicious domain.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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
  • 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/123?utm_term=christmas+carols+sheet+music+for+piano PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4414672/normal_600c38dc64f7b.pdfIn PDF document text
    • https://cdn.sqhk.co/fovomesit/hjYu4gf/old_school_r_b_music.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477379/normal_601d958186af1.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4490274/normal_5fc9157ca99bc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413125/normal_6021940e60560.pdfIn PDF document text
    • https://cdn.sqhk.co/ninevowa/Phhh4MA/disciplinary_letter_template_for_gross_misconduct.pdfIn PDF document text
    • https://cdn.sqhk.co/ramekodetuwe/iacVihV/zuwipuwuworodado.pdfIn PDF document text
    • https://cdn.sqhk.co/sovokeduseb/ihjgPie/fantasy_football_name_generator_female.pdfIn PDF document text
    • http://mujoxoluvisukid.getenjoyment.net/bpsc_mains_geography_question_paper_2020.pdfIn PDF document text
    • https://cdn.sqhk.co/jenetuwuda/Dtibpjc/cats_crash_arena_turbo_stars_free_online.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4423452/normal_5fc95bd71bc60.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/ladojenefe/1515966114.pdfIn PDF document text
    • https://s3.amazonaws.com/tapelu/jivurigilosalelisux.pdfIn PDF document text
    • https://s3.amazonaws.com/divelatoxa/nuxokovewofuxofofas.pdfIn PDF document text
    • https://s3.amazonaws.com/dotivaf/how_much_does_youtube_pay_for_live_streaming.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ee9760e1-860b-47fb-ad9a-98edec907fa5/30152078018.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2003bd4b-31a9-418d-8310-9f9e19de00dc/jutaxawapusifolofanokeniv.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/682d3d5e-f1c7-4727-8514-30e34fa89707/emergency_room_doctor_salary_florida.pdfIn PDF document text
    • http://solezod.myartsonline.com/which_institute_is_best_for_software_testing_in_bangalore.pdfIn PDF document text
    • https://s3.amazonaws.com/dojivewobasuval/14757142967.pdfIn PDF document text
    • https://s3.amazonaws.com/jirebonudur/gingerbread_house_candy_templates.pdfIn PDF document text
    • https://s3.amazonaws.com/vutame/camelot_full_movie.pdfIn PDF document text
    • https://s3.amazonaws.com/besafefaf/zivusowizajoxavas.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5b8e8516-b756-4c9c-8b55-76078854c13f/what_is_the_importance_of_choosing_relevant_literature_in_writing_a_research_paper.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/78ee3f94-a5f6-4dbe-9347-9790f8850390/how_much_does_a_tv_wall_mount_installation_cost.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_off00010290.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10290 5160 bytes
SHA-256: 11ad7c617e3e1ec96703524ba9a4949ea886976782606ce8503878f368d2482d
font_01_sfnt_off000113ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113ED 10272 bytes
SHA-256: 15e1b29a4b2f8b25f2adf561d8ca1500b6b988c2e34281d03771a37bcf6b1c62