Malicious PDF — malware analysis report

Static analysis result for SHA-256 26f6b34aee263419…

MALICIOUS

PDF

77.5 KB Created: 2021-04-18 04:10:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 206fba5130906724c85ba4dac5580487 SHA-1: 5edc8952b59d9e7f895262c8ad86202ecb2eaf08 SHA-256: 26f6b34aee263419fc852a4c6420ecbd55650daf631b04d4bb53a377aadfeb30
194 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of external links, many pointing to disposable domains, suggesting a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, appears to be a lure related to 'coding the matrix linear algebra through computer science pdf', likely to entice downloads of further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://dugedepap.ru/strik?utm_term=coding+the+matrix+linear+algebra+through+computer+science+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4417419/normal_6010a331619a1.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4425227/normal_5fce6c144ee93.pdfIn PDF document text
    • http://usesalle.xyz/264692630873thb3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4494668/normal_6025c4286a3df.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4498986/normal_606ea48d4ee92.pdfIn PDF document text
    • http://phtech.site/33216895953blv9l.pdfIn PDF document text
    • https://piworanup.weebly.com/uploads/1/3/2/6/132681558/9080420.pdfIn PDF document text
    • http://ozalupa.space/55772230694tfyv4.pdfIn PDF document text
    • https://cdn.sqhk.co/losajaro/CWgihgi/68917553207.pdfIn PDF document text
    • https://sokifavobal.weebly.com/uploads/1/3/4/5/134514189/wuguzesulezige-kugigori.pdfIn PDF document text
    • https://tanedozuwo.weebly.com/uploads/1/3/4/6/134644204/tugive-tazusudoladelub-todumedobomavon-tamadarupug.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4401540/normal_603bfbfc4dee7.pdfIn PDF document text
    • https://cdn.sqhk.co/xuzalolotagi/srjbrb2/tekik.pdfIn PDF document text
    • https://gajevorotaro.weebly.com/uploads/1/3/5/3/135329880/xezivabarofedi.pdfIn PDF document text
    • http://nout-prokat.website/wamaxevelujizuwezarojijuzj51np.pdfIn PDF document text
    • https://cdn.sqhk.co/pubodegosog/bhfigq5/banco_do_brasil_santos_dumont_mg_telefone.pdfIn PDF document text
    • https://cdn.sqhk.co/zudilubal/hbvbpgi/84344366736.pdfIn PDF document text
    • http://uspex22.online/food_wars_season_5_episode_13_wikijozg3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4419437/normal_604138220f189.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4465938/normal_5fdf491171515.pdfIn PDF document text
    • https://cdn.sqhk.co/wikaraxixi/RwhcGgd/53651835723.pdfIn PDF document text
    • https://denagivar.weebly.com/uploads/1/3/1/3/131383646/cae2ddd335a.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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_off0000efc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFC1 5684 bytes
SHA-256: 9aa1411d8be12e0c20a05e56769c6bf4eaf8ca8a1572e55e3909f7aa4df314a3
font_01_sfnt_off000102ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102EC 10756 bytes
SHA-256: 583304c480e9ff912f534f9ee9ab8f3fe975e9f98ef0fcf406249b3de222f02c