Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b6ff817cc7652ed…

MALICIOUS

PDF

80.7 KB Created: 2021-03-24 22:18:06 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: e5f679b50793c7cd01f4903de1941bcf SHA-1: 8495f36f24d47be39d5724c7fbc30ffcd2c40e5d SHA-256: 1b6ff817cc7652ed96042c7f44a69951be8555c22c784001539dc198eb60fa85
186 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 0.9997

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://vilenefex.ru/123?utm_term=irs+guidelines+for+401k+loans PDF link annotation
    • https://zoxiniguve.weebly.com/uploads/1/3/4/5/134584112/jibibumenejox-fivetufabisi.pdfIn PDF document text
    • https://duruzamuxe.weebly.com/uploads/1/3/2/3/132302842/bipunave.pdfIn PDF document text
    • https://nigoriwidoke.weebly.com/uploads/1/3/5/2/135296580/77e8fe077647291.pdfIn PDF document text
    • http://zonokiwuwagupu.getenjoyment.net/23110400921.pdfIn PDF document text
    • http://wosatonosefenaw.iblogger.org/vmware_workstation_12._1_linux.pdfIn PDF document text
    • http://dajexori.mypressonline.com/fididilidodadegewejoma.pdfIn PDF document text
    • http://julajaz.22web.org/bolens_38_13.5_hp_lawn_tractor.pdfIn PDF document text
    • https://tewawabuse.weebly.com/uploads/1/3/1/4/131437503/kufisilopegedur_kurutap_zunededipepa.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://7605c768-a471-4169-85a9-0dab509fd250.filesusr.com/ugd/20ab23_3be14f8fe4494614b688aae60789c7db.pdf?index=trueIn PDF document text
    • https://7f793f8f-877f-420e-851b-8bae9ea62a4d.filesusr.com/ugd/78c764_341fcfb4f4b44030ab8125a5aba3f54d.pdf?index=trueIn PDF document text
    • https://54a0e2cb-796f-4f80-9aaf-d11633176b06.filesusr.com/ugd/b0c554_af5436bab6f143a7b3c6e3d57491ab12.pdf?index=trueIn PDF document text
    • https://348ddb29-83e1-4812-94a1-743b72ef9b42.filesusr.com/ugd/23b571_5b44bc12dc854d4088cc4864ddad50ae.pdf?index=trueIn PDF document text
    • https://be1d055c-b83b-422e-9e68-1bf13cef350c.filesusr.com/ugd/5b1e3c_cc78cde5dc584f85984b9ffe685bdee1.pdf?index=trueIn PDF document text
    • https://45f91bdd-2b68-4e60-ae2c-b14373ae5332.filesusr.com/ugd/0d089b_57d5d31021254821b724d78693311492.pdf?index=trueIn PDF document text
    • http://tepominofujemo.atwebpages.com/22323163183.pdfIn PDF document text
    • https://83d7d1d1-3661-4158-a2cc-78aa4aa39d08.filesusr.com/ugd/163759_807e61e8604c48f89d74a4b492e20c7b.pdf?index=trueIn PDF document text
    • https://b993c520-4fc9-488d-8dda-35d8b3dc2713.filesusr.com/ugd/6f5492_a462de9e907044dd89f9b750211dc67f.pdf?index=trueIn PDF document text
    • https://ee60c613-3dd1-430d-b711-08e3dcbf0273.filesusr.com/ugd/19ce5d_b522b3ba5cf74641b9ae02575fe8613d.pdf?index=trueIn PDF document text
    • http://fologipuvug.epizy.com/buwituro.pdfIn PDF document text
    • https://bcd7deca-fd5d-492b-a220-d373ca515bc9.filesusr.com/ugd/12f4eb_38a7419df17944b9b53d23e68081be01.pdf?index=trueIn 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_off0000fd44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD44 5356 bytes
SHA-256: 0241908364a3a0374c1c55a3865457a8bc9087aa5beeae2f512a11349bdca87d
font_01_sfnt_off00010f99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F99 11100 bytes
SHA-256: e9251e546f894f576e6190100868448c47ee61bfff3d14fdf5eef0d360c5b01b