Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f3c178c9405644d…

MALICIOUS

PDF

91.5 KB Created: 2021-03-24 23:12:13 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 6e1c166e6e86f895b4ff31f39d4f4ded SHA-1: 1c2ccc8021bd690f1a78d083f1bc972c61c8931a SHA-256: 8f3c178c9405644d1b0508b93982a225e37336be4774cc6cff11595bb0e4d31e
226 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 0.9998

Heuristics 7

  • 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.
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://xezojetit.ru/wix?keyword=if21053+teach+them+spanish+5+answer+key PDF link annotation
    • http://mkr-olimp.info/cialdini_influence_the_psychology_of_persuasion_summaryvilci.pdfIn PDF document text
    • http://fastgetme.online/13176453642893m1.pdfIn PDF document text
    • http://bezivodediz.iblogger.org/aortic_aneurysm_guidelines.pdfIn PDF document text
    • http://privateguardingserviceagainstdanger.site/76345258712vm6zb.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/d5b2b054-ee22-4cf4-8b0f-7d9454ae9359/cnn_latest_world_news_now.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9113b0ad-47be-41fc-a322-fc4983c7890a/zokibadikofekavi.pdfIn PDF document text
    • https://db532842-334f-4efb-8993-e67ec8f20ff5.filesusr.com/ugd/bc5be3_8c0ddb5cb22c4eb1bc880a3a89dbc73c.pdf?index=trueIn PDF document text
    • http://norilonabu.epizy.com/gitifogurogiwonojijabepa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0252353e-c636-4931-892d-6288408fea0e/gijituwa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d90b3f58-114d-43f6-868f-b970105710e5/how_to_update_astro_a20_gen_1_xbox_series_x.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/34ef29a8-7b00-46c2-819b-a06f73de4969/what_are_the_levels_of_ham_radio_license.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f8d990e6-ff1f-4613-94af-f1f047e30eec/how_to_reduce_metabolic_acidosis.pdfIn PDF document text
    • https://2a0daf8d-7d8f-48a8-9da6-1f2c606fcb3a.filesusr.com/ugd/adb9e1_100c36a97b2c40898ab0f9e39244d3c0.pdf?index=trueIn PDF document text
    • https://b54663a3-ff9d-4122-b75c-69b71428c9b0.filesusr.com/ugd/cfa91a_753314ec89664f1c979d6c7406094ceb.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/1c20d593-1691-4126-8e58-a0944885ed36/dks_model_1812_manual.pdfIn PDF document text
    • http://xomulaseropo.epizy.com/67908502393.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9c9f9ef0-5808-4f61-b0c0-65a215ea6d90/scary_stories_to_tell_in_the_dark_monsters.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7859c75e-7324-4729-8523-fcd90e6436c1/zemovalerufonodufod.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e8e62df1-e07b-4478-bc48-913f6442880c/canon_pixma_mp250_software_download_free.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_off0001240a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1240A 6032 bytes
SHA-256: 8ea1d7c3fa270020c6a01e66ce0e01b680da285a4ee95597a0afb98a63519366
font_01_sfnt_off0001388c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1388C 12104 bytes
SHA-256: c3fd99424174b81091f4a5856b099d604741bac9f89a5f76849f56caf7105903