Malicious PDF — malware analysis report

Static analysis result for SHA-256 dca401c77f6dc282…

MALICIOUS

PDF

86.0 KB Created: 2021-03-15 16:03:04 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 6a4ea7add937e43acfe89d4efe2f62ac SHA-1: 9c5753056bd7c37ca10b0420360ac808bbfbb208 SHA-256: dca401c77f6dc2820a1fa80a413915924b1576e55742a478bf7394add38d9023
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains a large number of external links, many pointing to disposable domains, suggesting a link farm designed to host malicious content or redirect users to phishing sites. The document body, though heavily obfuscated, contains text related to solving Rubik's cubes and mentions wkhtmltopdf, which is unusual for a security guide and may be a lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://gimoguvi.ru/strik?utm_term=can+you+solve+rubik+cube+without+algorithms PDF link annotation
    • https://cdn.sqhk.co/potasuregoz/Kji0sRH/kidobugazonon.pdfIn PDF document text
    • https://nelemiken.weebly.com/uploads/1/3/4/7/134704654/1845847.pdfIn PDF document text
    • https://pidowiwosuzaji.weebly.com/uploads/1/3/0/9/130969191/boduxadul-guzejeta-nuzuro-pikus.pdfIn PDF document text
    • https://cdn.sqhk.co/pobijejok/gghjaje/iconic_movie_scenes_to_recreate.pdfIn PDF document text
    • https://seporarutigofu.weebly.com/uploads/1/3/2/7/132741198/pawisarud-japetot-telibelozasup.pdfIn PDF document text
    • http://axecheat9.xyz/vupitisejezerijerupu4lgde.pdfIn PDF document text
    • https://cdn.sqhk.co/pegidago/hQijbhd/maximum_care_hospice.pdfIn PDF document text
    • https://cdn.sqhk.co/bowewulaxam/7BgjTjd/treasure_hunters_series_book_2.pdfIn PDF document text
    • http://instapriz365.online/coopervision_proclear_1_day_multifocal_fitting_guide7v14n.pdfIn PDF document text
    • https://jafedojinow.weebly.com/uploads/1/3/0/9/130969492/9774688.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/5eeada76-bbad-4710-bebf-970eb1534517/sap_system_security_guide_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/badaecbf-6f58-4eca-a783-1c823cd4e7f6/air-lap1142n-a-k9_setup_guide.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ad92860e-9d9f-4f65-af94-57dc734d5275/51290910381.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/28e7dea2-433b-440d-a820-cefeb1bbdb14/71178535488.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dcb4f512-18dc-46b5-ab0d-8182939d2826/craftsman_chainsaw_16_chain.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7eef335a-d42e-4c2e-846b-0bc037451456/55010890376.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2436237f-74da-4829-a900-12eef6f62feb/tisej.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a0d34837-acbd-4ef1-a38c-3b6b31770123/supportnintendo.com_error_code_51330.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4224db83-de92-45a2-a818-3d93b14c1410/after_we_fell_cast_trevor.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/75513a7b-985f-4001-804f-8a7402bb1ffc/panasonic_lumix_fz2000_preisvergleich.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5a6e1145-7248-4c10-8682-067e73b10432/pepokaxonalegalux.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e87a5b06-3b76-42f6-8dc4-8ff8eb33b07a/transact-sql_books_free_download.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_off000112e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112E0 5576 bytes
SHA-256: 29898de94de5ebee1c412384e80013ab40883f48af912c99ce87354b341e3c3e
font_01_sfnt_off000125cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125CF 10736 bytes
SHA-256: 009bdf298b8ac15c67644052abb2676730e7fc8e3bec51c6a5db19a3adefd1bc