Malicious PDF — malware analysis report

Static analysis result for SHA-256 37f54b080e63a791…

MALICIOUS

PDF

80.8 KB Created: 2021-04-08 06:48:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 5785ab0225a1163f212d2df4168b0b16 SHA-1: 5ee2a73d193d5a97a673243d5d3845423bc1c6c9 SHA-256: 37f54b080e63a79124fb997f93f174aeaa59a6523a3f7d3ea73990f8bf5d0265
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://jacksth.ru/123?utm_term=carotid+artery+stenosis+treatment+guidelines+2014 PDF link annotation
    • https://cdn.sqhk.co/zikufivol/f5hjsic/pinenasonozaxibamawaseko.pdfIn PDF document text
    • https://cdn.sqhk.co/zojixemem/hchjhhj/9631225866.pdfIn PDF document text
    • https://cdn.sqhk.co/nakunadubux/nNjdie3/javelin_master_7_days_to_die.pdfIn PDF document text
    • https://cdn.sqhk.co/fopujetoros/X6Fhgjf/gym_exercises_for_beginners_male.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/2e05296d-4ebd-4c9b-a316-5791d53526c1/bash_script_for_loop_file_list.pdfIn PDF document text
    • https://87c8fc71-818b-4167-bf0d-2ac3bc49ffd1.filesusr.com/ugd/f9d4cd_0543f97beefa47a2bd5e2d50e14aab7a.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c66f8be2-3f6c-4184-95a3-9bf98231ce46/graco_duoglider_swing_washing_instructions.pdfIn PDF document text
    • https://cf336f9a-6a79-4542-9269-5b62d6eb69dd.filesusr.com/ugd/1daf83_824e1493e122446c8a7082e9cf203e65.pdf?index=trueIn PDF document text
    • https://0df6220b-9630-4647-aab6-0d9db69b9d59.filesusr.com/ugd/8b97dd_b1ee7b8f63414977a83f5da8c7f92750.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/8a0b9c1f-a20f-4e79-a2e2-cb5de78acc96/physics_part_2_resnick_halliday.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9f1915b3-22fe-4977-95a6-f2e1b4c479cf/zifomozipegekaw.pdfIn PDF document text
    • https://e25b5f36-ee09-4010-8803-019b2853a23b.filesusr.com/ugd/c34eac_0045738189b844a7b6d177f0bc73939c.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/cea4d9b4-2816-45ec-b67e-954aeefbd790/36771024495.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c340df87-89fd-4e4d-9789-aedaa6e48b01/86199440193.pdfIn PDF document text
    • https://f87ce62f-3d5d-4c42-bff3-2e7d00444551.filesusr.com/ugd/72ed28_57a84645bede42299880e713281b95bd.pdf?index=trueIn PDF document text
    • https://8d67285a-e3c5-4820-bb1a-bb91ce1079a6.filesusr.com/ugd/d54300_a94b47fe6181494f9ceac17b2f80995d.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/79270471-53b7-4bc9-a47c-0862b5a26777/marine_fish_excretory_system.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d48b217d-667e-41fb-954e-c1514a9b6293/is_sword_art_online_a_harem_anime.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7730eec2-646b-46b0-abcd-9194b38ed6c6/buzisenunidomemejin.pdfIn PDF document text
    • https://fa3f2985-242d-4a4c-93c0-6adbfb259eaf.filesusr.com/ugd/8dbe7a_8e49e8b2be29496fbb61bf7d13feed14.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/5f8e3500-30f9-4e70-894f-56c235ce0ab2/63482478000.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_off0000fd4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD4A 5564 bytes
SHA-256: 393ec09eac25aa65e8645bc563d67943fbd70015a2155eeaa7f70a0fd6d629e8
font_01_sfnt_off00011030.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11030 11044 bytes
SHA-256: e5d47dd5256d1390dce6614cf9502b2bf981cf6d4f2e44e0d8de80c7430fd82d