Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf90c1d78b819107…

MALICIOUS

PDF

79.2 KB Created: 2021-03-20 14:26:06 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 2e746da1924de150d6df38f396c09f0d SHA-1: 8d85a2c59fa7f73f95a41bf1af486955b483959c SHA-256: cf90c1d78b819107acc1f0cc86f1d10aa96e5df68a7edcc82888cf38b13d54a6
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 0.9993

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
  • 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://jumiwimov.ru/strik?utm_term=discrete+probability+distribution+problems+and+solutions+pdf PDF link annotation
    • http://dewemopiwofim.22web.org/puzzle_and_dragons_z_monster_guide.pdfIn PDF document text
    • https://paxowudozu.weebly.com/uploads/1/3/6/0/136095727/guneg.pdfIn PDF document text
    • https://cdn.sqhk.co/xelajuwodaf/rgdgeja/kuxageboje.pdfIn PDF document text
    • https://papukelub.weebly.com/uploads/1/3/4/6/134666119/8672254.pdfIn PDF document text
    • https://cdn.sqhk.co/ketegobuto/hidrjcw/tuxejudun.pdfIn PDF document text
    • https://cdn.sqhk.co/mobirewin/hwgjhc5/another_word_for_love_letter_in_french.pdfIn PDF document text
    • https://cdn.sqhk.co/nokotadi/M90ggND/underhand_throw_lesson_plan.pdfIn PDF document text
    • https://jetukuzimol.weebly.com/uploads/1/3/2/6/132695660/noxivuxukipumu_kogitorijevive_sebelasut.pdfIn PDF document text
    • https://cdn.sqhk.co/motuxeneb/Njglhfj/twitter_login_codeigniter.pdfIn PDF document text
    • https://cdn.sqhk.co/zoravuzulop/fghrhgI/download_game_sky_baron_war_of_nation_mod.pdfIn PDF document text
    • http://gojazot.22web.org/what_does_the_table_symbolize_in_hills_like_white_elephants.pdfIn PDF document text
    • https://cdn.sqhk.co/xuxozowaki/yhbihjc/python_create_a_list_of_numbers_in_range.pdfIn PDF document text
    • https://cdn.sqhk.co/sarimotel/Ro6xja2/kunasosilovezer.pdfIn PDF document text
    • https://nipawivas.weebly.com/uploads/1/3/2/6/132680981/7977325.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/f00f879b-e8e2-487b-a7d3-e015843a9010/luvuvutizoduzaruk.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d70dcedc-4d0e-4424-a149-e1e8801eae14/suxerikuluja.pdfIn PDF document text
    • http://repawejijob.rf.gd/begate.pdfIn PDF document text
    • https://s3.amazonaws.com/vovopafubipu/les_miserables_abridged_james_k_robinson_audiobook.pdfIn PDF document text
    • https://s3.amazonaws.com/rebomedug/plantronics_backbeat_fit_connect_to_multiple_devices.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dd03a910-d8cd-46fd-8517-833cb3510440/sujotozadoxaxovogiru.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c5a38666-e82b-4da9-91e9-4322f5082697/how_to_assemble_luvlap_baby_bouncer.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1c6344f8-1728-485f-8d94-b1196551cafa/does_alkaline_water_flush_out_toxins.pdfIn PDF document text
    • https://s3.amazonaws.com/dogevazapiwediw/wopoxalujifa.pdfIn PDF document text
    • http://nawopadawejiw.epizy.com/english_b_guide.pdfIn PDF document text
    • https://s3.amazonaws.com/popisiburewixuj/maximum_principal_stress_theory_of_failure_was_postulated_by.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_off0000f52e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF52E 5540 bytes
SHA-256: da609fe83fe8ad552e6283dc51395ae442e50f5aecac28f32e53ea290fc665b8
font_01_sfnt_off000107fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107FA 11304 bytes
SHA-256: d9126169adca51ac1d570b08a728ed718ed531874ddeb0a217a3848def167e62