Malicious PDF — malware analysis report

Static analysis result for SHA-256 4dbdad94233864f1…

MALICIOUS

PDF

81.7 KB Created: 2021-03-10 21:23:42 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 2a2b57d451148ac3904012e0875a91b2 SHA-1: 9e7e3348b24403eedcc671c188b118bb492458a3 SHA-256: 4dbdad94233864f188884764b40fe2bbf9013b197d84821fbada0169afcc1f57
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF document was flagged as malicious by 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 0.9997

Heuristics 5

  • 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/award?keyword=ejercicios+para+aprender+ingles+para+ni%25C3%25B1os+pdf PDF link annotation
    • http://kataeta.club/memoji_sticker_whatsapp_iphone_ausschaltenyi72g.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4424405/normal_6048a3b0a4cdd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4373241/normal_6034d33fbbc8e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4381321/normal_5fe2e3e441af0.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4465151/normal_5fcf2c01dd1f9.pdfIn PDF document text
    • http://experiment.website/facebook_marketplace_local_cars_trucksdttcm.pdfIn PDF document text
    • http://theporte.xyz/book_making_software3z8jg.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://afa032df-bfad-47da-a9c8-c79260182993.filesusr.com/ugd/6f9b04_73b4db1c0b954ad1a4780ef533bb4dcc.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/3f6d32da-bac4-4323-8ec9-835b068e4465/5._how_might_different_types_of_stressors_affect_your_health.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5765929e-0055-4cc3-834b-3499345fc6ce/autocad_viewer_for_mac_autodesk.pdfIn PDF document text
    • https://983c8978-ad56-435f-a988-47358aa6040c.filesusr.com/ugd/06a663_1d702f037b7d4ba3be30540aabda3562.pdf?index=trueIn PDF document text
    • https://0fc0baf9-b884-4fcd-968e-f93c0f938930.filesusr.com/ugd/68ec51_bbceec97e9f3479995769bb2ff81f728.pdf?index=trueIn PDF document text
    • https://7fad2989-91b8-457c-89bc-9a0e7aeef19f.filesusr.com/ugd/b03ff3_3b14c1bc43ac4be3a5a4b17ac3611a92.pdf?index=trueIn PDF document text
    • https://f8d4b294-f952-4a11-85e8-0a3036f9bdaf.filesusr.com/ugd/ad8f3a_540775c3f92c447d80640c27396f2eae.pdf?index=trueIn PDF document text
    • https://769966b8-4adc-437e-bba8-f198cf6e171b.filesusr.com/ugd/41a0b6_7145180cc84d4f05b736e51b45cd4a38.pdf?index=trueIn PDF document text
    • https://01c19f78-c7d0-441a-b56a-8672493f87de.filesusr.com/ugd/9d66c7_0254313e657747e6a1c2ee1ca04f47ad.pdf?index=trueIn PDF document text
    • https://0f926834-650c-4d5a-b53c-ad60ae412ccc.filesusr.com/ugd/6a44d8_c00bf0cf022a4b27b2baf6202b3948b6.pdf?index=trueIn PDF document text
    • https://6c639bf1-704a-4500-b661-329758898742.filesusr.com/ugd/02d620_289e56395c65442f9491c35958556275.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/e605706d-85a1-432c-a20a-a24149de9450/9654634508.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/def75c10-57f9-46dd-a4aa-985627ed0644/50712384478.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e750.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE750 5568 bytes
SHA-256: 9203c298d15b33049c5fc1ec2a3003af71f2ce5a3b7a24c52774de6eb0afc79f
font_01_sfnt_off0000fa18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA18 12024 bytes
SHA-256: 508fa4f53f60cbd153f9a0b2c24b8a3be42cd33b8d91efed5a982e0d3247c2b2
font_02_sfnt_off0001211f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1211F 16312 bytes
SHA-256: 531e37f64a2e7dc3bfb257675d9e6c644c7b1597f33ba9a969cd005a7ed65660