Malicious PDF — malware analysis report

Static analysis result for SHA-256 2b6d153d60f04f76…

MALICIOUS

PDF

80.8 KB Created: 2021-03-28 06:35:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-02
MD5: e998d46dc8e42e9af0454c236a9e2c63 SHA-1: e7fe6e0e626167f33ff387270273f4a7b790aad9 SHA-256: 2b6d153d60f04f768d0cdea6d17c424482f5a42faaf2454b49643201a57242c0
186 Risk Score

Malware Insights

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

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains a large number of external links, many hosted on disposable domains, suggesting a link farm or redirection scheme. One embedded URL points to 'midufefew.ru', which is likely part of a phishing or scam operation. No scripts were extracted, but the PDF structure itself is used to host and distribute these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://midufefew.ru/123?utm_term=brain+teasers+for+teachers+with+answers PDF link annotation
    • https://kinijanara.weebly.com/uploads/1/3/4/5/134585029/badulesotubuv.pdfIn PDF document text
    • https://nezasofesaz.weebly.com/uploads/1/3/5/9/135961661/2892710.pdfIn PDF document text
    • https://dapadode.weebly.com/uploads/1/3/4/6/134646205/sulojulariwulara.pdfIn PDF document text
    • https://muxiduxipa.weebly.com/uploads/1/3/5/3/135319221/1777761.pdfIn PDF document text
    • http://vatamulejuvovi.22web.org/como_hacer_una_auditoria_informatica_ejemplo.pdfIn PDF document text
    • https://voguxobone.weebly.com/uploads/1/3/1/3/131379379/33dfbb6a0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4482648/normal_601c79d96634b.pdfIn PDF document text
    • https://gixusikowolo.weebly.com/uploads/1/3/4/8/134898106/lewomofobur.pdfIn PDF document text
    • https://vilamewu.weebly.com/uploads/1/3/0/7/130775649/napere-fukinakuj-nizukulap-goguzo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421201/normal_6041c8b59714f.pdfIn PDF document text
    • https://rexenupe.weebly.com/uploads/1/3/5/2/135299979/6630281.pdfIn PDF document text
    • https://wezinifagewugi.weebly.com/uploads/1/3/2/8/132815004/waludedido.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://9305c775-266c-4126-9ef9-90a5cffee957.filesusr.com/ugd/c3f88d_2567df7e192b4c51ab9b1f625dc8cfcf.pdf?index=trueIn PDF document text
    • https://80b2a579-f9ed-4aa0-b91a-ac3c8973c086.filesusr.com/ugd/353d00_bff8701c8e0b4e1db012384673544e18.pdf?index=trueIn PDF document text
    • https://b4e79a3f-0083-4b26-8056-4fe87fb46dfd.filesusr.com/ugd/332c1b_6a8896c4d69b4282b5332cd7bc628ed2.pdf?index=trueIn PDF document text
    • https://3b044092-e341-4c69-a8e2-52b14fc1865f.filesusr.com/ugd/370021_c53ec8b7fe2344e28b86962935595482.pdf?index=trueIn PDF document text
    • https://c948e902-2437-43f3-9f1e-7aaad30688a7.filesusr.com/ugd/464a75_0aded8ba419a41628570ed459b0e0a3c.pdf?index=trueIn PDF document text
    • https://af0fe010-594a-4ec7-a26b-e2d78e33490d.filesusr.com/ugd/7d2910_fe22dd348fdd4d5baa02d8a1ab09138e.pdf?index=trueIn PDF document text
    • http://rigawuseterozow.epizy.com/what_is_the_best_juice_to_make_for_weight_loss.pdfIn PDF document text
    • https://4eb3a9b5-ca6a-4b2a-896e-878abc754f3b.filesusr.com/ugd/f1ab86_f96bd413974f420585bc4e1d3ba7cc28.pdf?index=trueIn PDF document text
    • https://113c517c-d7b0-4b36-99d7-6722bcb7ef36.filesusr.com/ugd/8e66a5_6893270c1c1847f88e0ccd5690391fae.pdf?index=trueIn PDF document text
    • https://88749095-6fd7-453f-8e8a-15b48fe47dd1.filesusr.com/ugd/e4d7df_4a396eeeb2de44a3a78dc416b75fd711.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_off0000ffb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFB5 5076 bytes
SHA-256: 3cd27f2a3dd8a1c2c540974d97b99988eb07606885b17662492a7eedc4f4ab1c
font_01_sfnt_off0001110a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1110A 10672 bytes
SHA-256: 20e2ad9834fc9f06824cc274e61215560aef9e373005c396684f34cbe6db68dd