Malicious PDF — malware analysis report

Static analysis result for SHA-256 920538809aa53ea1…

MALICIOUS

PDF

149.3 KB Created: 2021-03-31 08:42:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 92126da612f3c44cf0d6f82def24ea0e SHA-1: dda7538a188d0eeacfa9f8b0a8673445cc58ecff SHA-256: 920538809aa53ea1e6d7fc00998385a642c5d2344371df90da9b47196847aa0e
144 Risk Score

Malware Insights

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

The PDF contains a high-severity heuristic indicating it's an SEO UTM redirector link, disguised as a worksheet answer key, leading to the URL https://golowaki.ru/wix?keyword=modern+marvels+acids+worksheet+answer+key. ClamAV also detected this file as Pdf.Phishing.Trojan. The ML classifier output of 0.976 further supports its malicious nature. The document body is heavily obfuscated, but the presence of external links and the ClamAV detection strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9760

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://golowaki.ru/wix?keyword=modern+marvels+acids+worksheet+answer+key PDF link annotation
    • https://cdn.sqhk.co/rodoruwuwab/NXPKGjc/26502976932.pdfIn PDF document text
    • http://baby-slings.ru/25070255576sd87g.pdfIn PDF document text
    • http://firstflirts.site/5267764718947jgt.pdfIn PDF document text
    • http://phillipen.online/native_instruments_maschine_mikro_mk3_usedpu9uz.pdfIn PDF document text
    • http://br1.red/warehouse_safety_bulletin_board_ideasvbcvo.pdfIn PDF document text
    • https://cdn.sqhk.co/rorajakura/bGiegjq/download_crack_city_car_driving_1._5._8.pdfIn PDF document text
    • http://cz-nitrof.website/cardinal_and_ordinal_numbers_chartetu1f.pdfIn PDF document text
    • https://cdn.sqhk.co/naxisedomak/aWgegdh/super_idle_hero_lumberjack_adventure_pigeon_forge_tn.pdfIn PDF document text
    • https://cdn.sqhk.co/wetilusogaki/gVCigIU/fumukezirovumetipesirarof.pdfIn PDF document text
    • https://cdn.sqhk.co/motulobugaji/fLjiLgd/39582425137.pdfIn PDF document text
    • http://toppiksnack.xyz/dunkin_donuts_iced_coffee_calories_with_almond_milkaecjj.pdfIn PDF document text
    • http://shoppermarket.online/wajuzusoranetn2vol.pdfIn PDF document text
    • http://kittyplay.online/how_to_find_number_of_atoms_in_a_given_massyhczr.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/savukojubusum/what_is_the_main_idea_of_the_book_enemy_pie.pdfIn PDF document text
    • https://s3.amazonaws.com/liwara/87708572898.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ade9acfc-471a-46ac-8f54-29c6d91f0aea/68917364875.pdfIn PDF document text
    • https://s3.amazonaws.com/fasudikek/pedidomo.pdfIn PDF document text
    • https://s3.amazonaws.com/fuwawibu/20642039687.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3832be51-43f6-43f5-9431-af4099fb5f9a/spyhunter_4_full_download.pdfIn PDF document text
    • https://s3.amazonaws.com/defujo/advantages_of_labour_relations_act_in_south_africa.pdfIn PDF document text
    • https://s3.amazonaws.com/takebemanijewok/bsf_pay_slip_information.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c77eb98f-27b8-4d22-ad95-37b6bde82d91/mn_dmv_drivers_license_record.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/86d944d8-f640-468c-b5f3-7021728c7915/97514746645.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/112f0e0a-da64-494f-bfff-53fc0e33c0db/zexuxirevadamiriza.pdfIn PDF document text
    • https://s3.amazonaws.com/vidadaviwal/zoninaxunano.pdfIn PDF document text
    • https://s3.amazonaws.com/filidabut/weferexikug.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001c6d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1C6D3 17244 bytes
SHA-256: 1345cb64ee5eb8981adad2adff2e63d991eed12da45589f2e996591b6fec46a0
font_01_sfnt_off0001fdf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1FDF8 5504 bytes
SHA-256: c1c279315ee8b0bda2e821d1cab61c380817de061b89494e3d35575c492a01ed
font_02_sfnt_off0002109c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2109C 1800 bytes
SHA-256: 6d2a3a16cc464ce72cf05976c7f96a31c93af2202e0dc760c37a694345e222ee
font_03_sfnt_off0002192c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2192C 13264 bytes
SHA-256: 252069df9f8ae51006e7682c5eaaa1186e404b9b5482e9a68d6e3a9b76920885