Malicious PDF — malware analysis report

Static analysis result for SHA-256 dbd4ab6bac5366b7…

MALICIOUS

PDF

102.4 KB Created: 2021-03-20 22:22:50 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: d916a9e6d6e04ddb5a09cc469fd11201 SHA-1: cedbd226b291bf72dedcdb19a9aa4262f91c04b1 SHA-256: dbd4ab6bac5366b7abf7418771c886fbc4590114f7b33c3219939554c94e4fd3
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the PDF structure itself is indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://vilenefex.ru/123?utm_term=edital+prf+ultimo+concurso+pdf PDF link annotation
    • https://rinezafuwokof.weebly.com/uploads/1/3/1/4/131437641/zitonisoj.pdfIn PDF document text
    • http://sellamorem.com/adding_and_subtracting_complex_numbers_worksheet_docnr7cp.pdfIn PDF document text
    • http://esplus.pro/sony_hdr-cx240_review60cqv.pdfIn PDF document text
    • http://liko-sneakers.com/742448598525vk2m.pdfIn PDF document text
    • http://frontend-developer-azaynullin.site/201930758281hmly.pdfIn PDF document text
    • http://evgeniy-semenenko.ru/44327695171yvat7.pdfIn PDF document text
    • http://tk-time.site/naxexedaxitatakizurareduvolh23.pdfIn PDF document text
    • http://gratoraama.space/39260409117rweg5.pdfIn PDF document text
    • http://markettop.pro/kawuvosesuvinigosasapua32d4.pdfIn PDF document text
    • https://geridaradekod.weebly.com/uploads/1/3/1/4/131437552/9487110.pdfIn PDF document text
    • http://nikaold.site/ncert_solutions_class_9_science_chapter_7_noteskcwi0.pdfIn PDF document text
    • https://zikamesezelili.weebly.com/uploads/1/3/4/8/134857079/buzodol_gejaxosizozil_zepasubipadive.pdfIn PDF document text
    • http://rrrrkkkkk.space/esl_speaking_board_gamespskzd.pdfIn PDF document text
    • http://myfavoritesun.xyz/bivemimamuxigumimikavamykd64.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/1a300e24-76a1-40d2-85c7-badce51ab3cf/kakunotaterusakulavife.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/08b715d3-088d-4dca-8a19-5e0ed045ddc5/is_slavery_illegal_in_the_united_states.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/424f4b66-dcea-4b69-8243-36768e9bf79e/el_pollo_loco_keto_menu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7e6164c0-d434-42a7-8a06-6bd8032ed930/nigun.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e43f3990-e70b-4185-81e9-201aab534826/kindle_fire_hd_7_3rd_generation_cyanogenmod.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fe181d8a-6650-4055-8758-e2ef15394b13/jidiretunadorolebeni.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00013c1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C1A 5020 bytes
SHA-256: 324340e37f6149996299b01182fb9ae0203840c90c0ab7fbb6c5cc53a4f99cb4
font_01_sfnt_off00014d0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14D0E 15600 bytes
SHA-256: dbf7a4874dcd8e1cbf7270b32bd6dc944f636a3f5629fa25987d33232e0cb4f4
font_02_sfnt_off00017c07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17C07 4324 bytes
SHA-256: 1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361