Malicious PDF — malware analysis report

Static analysis result for SHA-256 19035dc26cc5b004…

MALICIOUS

PDF

81.9 KB Created: 2021-04-06 15:19:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: d353ac35db37b3f47accc3309b789643 SHA-1: 25586a937c99490e95a812e291171ff09ccd0eac SHA-256: 19035dc26cc5b004fde069a7f2290a4cc2bd4d9ce775259b8f8c900256ae83fa
126 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which are hosted on disposable domains and flagged as part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically phishing or malware distribution. The document body, though heavily obfuscated, suggests a lure related to 'shark dichotomous key worksheet answers pdf', aiming to trick users into visiting these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://nipisod.ru/strik?utm_term=shark+dichotomous+key+worksheet+answers+pdf PDF link annotation
    • http://tanubujurutemut.scienceontheweb.net/offset_printing_press_company_profile.pdfIn PDF document text
    • http://xojuxelase.medianewsonline.com/jolejuwekijugula.pdfIn PDF document text
    • https://cdn.sqhk.co/xetasenuwoji/jcjsJ3A/fosopaxisojor.pdfIn PDF document text
    • https://cdn.sqhk.co/dikapagoloza/h6J3ojb/pocket_tanks_deluxe_weapons_pack_free_download.pdfIn PDF document text
    • https://cdn.sqhk.co/rigizisojix/aghgjjb/the_amazing_world_of_gumball_magic_notebook.pdfIn PDF document text
    • https://cdn.sqhk.co/mekoposa/jjfgebO/resume_template_editable.pdfIn PDF document text
    • http://fegivate.medianewsonline.com/advanced_computer_architecture_solution_manual.pdfIn PDF document text
    • https://cdn.sqhk.co/tuledapozato/ahbgjCF/49394849196.pdfIn PDF document text
    • http://lidedapomegila.iblogger.org/blank_book_review_template_ks2.pdfIn PDF document text
    • https://cdn.sqhk.co/ruxuxona/jdhh7u4/xijolonaretiwot.pdfIn PDF document text
    • https://cdn.sqhk.co/geroterunetu/qF77jje/night_of_the_full_moon_witch_guide.pdfIn PDF document text
    • https://cdn.sqhk.co/vilosezuj/jjGheJy/36948886357.pdfIn PDF document text
    • https://cdn.sqhk.co/lilomovetum/Sq1Avha/20715788204.pdfIn PDF document text
    • https://cdn.sqhk.co/genopeno/iiivB3q/90709812268.pdfIn PDF document text
    • https://cdn.sqhk.co/sejujona/WVjgqje/nyan_cat_lost_in_space.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://tebuwawezizafes.onlinewebshop.net/edit_file_tool.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5ea8f41e-e9e8-401b-85cd-4ba2f552e6a2/sentry_safe_reset_code_without_manual.pdfIn PDF document text
    • http://zigatikix.rf.gd/45767599027.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a0d6d767-6598-4c96-bc93-04df3c48a34c/stephen_king_book_covers_1980s.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c2761ae3-6f41-41a9-964f-a4a652b490b5/cashier_training_checklist.pdfIn PDF document text
    • http://donijexufenu.onlinewebshop.net/how_do_i_know_what_size_kenmore_refrigerator_i_have.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dfbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFBD 5604 bytes
SHA-256: 63dd6b6b66c6f5e825db3dfd94f087607bf6f82e6c5d4c48ae344153b1479ab1
font_01_sfnt_off0000f2b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2B4 9892 bytes
SHA-256: 41a3fd2f568a60c15f652552800473073d9b335f1a858de16556e8c5acf40ae0
font_02_sfnt_off000114a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114A8 16160 bytes
SHA-256: 71fec8a3adfe41455811528c654ef740a0d97889ddd19e39e153b04b7507b7f0
font_03_sfnt_off000129a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129A3 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378