Malicious PDF — malware analysis report

Static analysis result for SHA-256 616da3969ff5a52b…

MALICIOUS

PDF

77.1 KB Created: 2021-04-15 15:46:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: fc0e314c75497e00e1999fc35f823628 SHA-1: 51583fce32d8f4584a0f8a767e1fd45a6ad9219f SHA-256: 616da3969ff5a52b5e9666ce515491755f7719f1627e40ac9df6b11662fdccf3
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was identified as malicious by ML classifiers and ClamAV, with critical heuristics indicating a large farm of external links. These links, such as 'https://leonvi.ru/strik?utm_term=how+to+use+crate+divider' and 'https://cdn.sqhk.co/fekurisakez/fgePUXX/influencer_marketing_companies_in_delhi.pdf', are likely used to redirect users to phishing sites or download further malicious content. The document's structure and the presence of numerous external links strongly suggest a spearphishing attachment attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://leonvi.ru/strik?utm_term=how+to+use+crate+divider PDF link annotation
    • https://cdn.sqhk.co/fekurisakez/fgePUXX/influencer_marketing_companies_in_delhi.pdfIn PDF document text
    • http://kopaburak.sportsontheweb.net/ruraveruretijag.pdfIn PDF document text
    • http://tepifugamokeg.medianewsonline.com/fofimaxidoxasabeweloxir.pdfIn PDF document text
    • https://cdn.sqhk.co/fagaxirupunu/fjuCidc/gavam.pdfIn PDF document text
    • http://jiwimejikigigu.mywebcommunity.org/bible_malayalam_file_download.pdfIn PDF document text
    • https://cdn.sqhk.co/kagumuzom/hgjghfj/anlage_vl_2017.pdfIn PDF document text
    • http://lakujalinifibo.mypressonline.com/zovodutamo.pdfIn PDF document text
    • https://cdn.sqhk.co/losokifape/aJlhbxv/gabasutujosonus.pdfIn PDF document text
    • https://cdn.sqhk.co/kamozipu/hejbiiL/zogitowose.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/c10cbfad-61c7-458e-bb42-e514a76dfee4/othello_book_review.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/59417cee-2c2e-4973-9120-8865e15165e1/griffiths_introduction_to_quantum_mechanics_3rd_edition_solutions.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4e8fe3b4-1fe6-4001-b62c-25a9f1600b08/what_is_the_mood_at_the_beginning_of_the_fall_of_the_house_of_usher.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ac9aff42-ac39-4f18-b678-1800dcdd798c/wenela.pdfIn PDF document text
    • https://680e7e7f-99bb-4309-8a01-ecc910dc7690.filesusr.com/ugd/717a42_6629191720f74b52a550f214c6cdbd16.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/994bcac5-8d69-4e2f-a036-4b6b2a40f426/tivomutigemosadabixe.pdfIn PDF document text
    • https://32b33340-d9da-4ef7-b3bd-a0ac5134eb71.filesusr.com/ugd/adfa6f_cc6d75410ec049869f39f4ebbdb93311.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/bd63daf7-8165-424f-892b-4459d8ff33f4/numomagulumiripazejepob.pdfIn PDF document text
    • https://e62d90d9-845b-491d-b9b1-804d55ccd6e6.filesusr.com/ugd/6af1ed_9c7dc39f5c204535a4833ef89c65589f.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/6bdf730b-c1e4-4193-99bf-10bf3c0b1ed7/56225982184.pdfIn PDF document text
    • https://d17f4099-ecc1-42b1-9c73-51521793457c.filesusr.com/ugd/4a2613_005a69ae278f4ea0affd5c2f5f13a872.pdf?index=trueIn PDF document text
    • https://1d942ef5-affb-47d8-8f99-70a3d187b733.filesusr.com/ugd/3283b0_dff3a33892ba4ebeb872d4f162a73408.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/aaf47133-38ef-46e6-98e4-032866e773ca/mokobavifif.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/660606c0-1ab1-4ba7-9e84-2aeb8f93d156/does_garmin_vivofit_jr_have_gps_tracking.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_off0000f314.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF314 5012 bytes
SHA-256: cf1f3ecba5c0857918cda878c987a0350d319c358125d5ba9683dd22f93af9f8
font_01_sfnt_off00010445.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10445 10044 bytes
SHA-256: 176e6fed663a2565797e9a418d4925feac6b89d26a544c55458e5f8736a288c1