Malicious PDF — malware analysis report

Static analysis result for SHA-256 921041c50bd55681…

MALICIOUS

PDF

83.0 KB Created: 2021-06-07 10:21:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 1b482cddf5b3468696b60c372df32c05 SHA-1: ec5401285d89fefa0041feb2d082f1e5c184bdbc SHA-256: 921041c50bd55681411774cb790f900051b38681589395f4ae91e3cbd9b49dbc
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://catamma.ru/pbw?utm_term=dexter+season+4+subtitles+download PDF link annotation
    • https://lasomuvexovip.weebly.com/uploads/1/3/0/8/130813571/6960588.pdfIn PDF document text
    • https://perelixaji.weebly.com/uploads/1/3/4/8/134881923/3545467.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4457592/normal_602730bc37390.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382771/normal_5fdc6c3cb782c.pdfIn PDF document text
    • https://perelixaji.weebly.com/uploads/1/3/4/8/134881923/34394c30.pdfIn PDF document text
    • https://tunilixagipibi.weebly.com/uploads/1/3/5/3/135304468/44c34fcf6b75.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4415052/normal_60b216fe719ba.pdfIn PDF document text
    • https://lufisadoxusixa.weebly.com/uploads/1/3/4/5/134583632/xisogugokaw.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4425506/normal_6066d795bca1b.pdfIn PDF document text
    • https://nimizinimaji.weebly.com/uploads/1/3/4/7/134703428/9dc0044b398.pdfIn PDF document text
    • https://wojadamizaxit.weebly.com/uploads/1/3/2/6/132681796/2524002.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369189/normal_600f1ede6d023.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/4c2236e1-960f-42ea-9b69-54a517e3371c/ludamude.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/be1c7923-af65-4891-98d0-f269d12886ac/salezubeza.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/22e495ed-87e8-46b0-be71-232bedeada3f/93389384427.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/903951c1-85f1-4dff-a5b8-1c619d9ea41b/ti_nspire_cas_calculator_online.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1dc73d49-cbbb-4143-9523-135842025226/10829725911.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/89f57e08-c83e-4f93-a8d9-e3236ce4e71c/webezimarenu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b10d98b9-72eb-4567-995e-984d769f7482/86714077855.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b14cdd11-015f-497b-99e0-12b06e52e342/el_amante_japones_isabel_allende_critica.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://www.geocities.com/mitra_anirban/hobbies.htmGNUIn PDF document text
    • http://www.gnu.org/copyleft/gpl.htmRegularIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dc5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC5D 5204 bytes
SHA-256: 2dd7e77f2039638ea0c479395386cd1300a2a111019f65d9a04339ce8b343c49
font_01_sfnt_off0000ee39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE39 13836 bytes
SHA-256: 7ed6e8c8ad5067ae61fc4eefb6a5ee46712b496acafa0f583a159a4f1eb02f30
font_02_sfnt_off00011970.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11970 10196 bytes
SHA-256: 769c2fd6fa0c407950c0d15afaff360c575a11f1194bea0d2a8c8413b2ee8d03