Malicious PDF — malware analysis report

Static analysis result for SHA-256 8831b121e96b6143…

MALICIOUS

PDF

78.6 KB Created: 2021-03-11 23:29:06 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 45d039798c225a22cf20a988993eabd2 SHA-1: 777948265408663db07a277d779034e7150fc4eb SHA-256: 8831b121e96b6143176401fd4eca2064b6edcbf61f8f9ea41d29acf8bd29940c
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable domains, as indicated by the PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the nature of the link farm suggests it could be used to distribute further malicious content or lead users to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9967

Heuristics 6

  • 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.
  • 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 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://soxebez.ru/123?utm_term=basic+engineering+graphics+questions+and+answers
    • https://komiwafaka.weebly.com/uploads/1/3/2/7/132712661/f6de3943.pdf
    • http://dofujifeluradep.medianewsonline.com/suzokuke.pdf
    • https://nazuvunu.weebly.com/uploads/1/3/4/4/134438845/minelobelidoxosafo.pdf
    • https://zekufizow.weebly.com/uploads/1/3/0/7/130775694/09f699.pdf
    • http://lorakuze.sportsontheweb.net/5221683536.pdf
    • https://cdn.sqhk.co/wuwexosul/hdrgd1r/turbo_drift_3d_car_racing_2017_apk.pdf
    • https://cdn-cms.f-static.net/uploads/4366031/normal_604a13005665c.pdf
    • https://satukaxel.weebly.com/uploads/1/3/5/3/135346341/vutuv-woralixawa.pdf
    • https://noromilo.weebly.com/uploads/1/3/4/5/134587763/gidixebitori.pdf
    • https://cdn.sqhk.co/gituridewo/gf8gihf/home_electrical_wiring_diagram.pdf
    • http://pinegobojefo.getenjoyment.net/fufiraguk.pdf
    • https://cdn-cms.f-static.net/uploads/4443802/normal_603fb94e21744.pdf
    • https://cdn-cms.f-static.net/uploads/4387242/normal_603eb4b20f501.pdf
    • https://cdn-cms.f-static.net/uploads/4402712/normal_5fe7acfc802da.pdf
    • https://cdn.sqhk.co/giganopof/MahjDih/nail_art_ideas_for_short_nails.pdf
    • http://vipimuxatomefi.medianewsonline.com/los_7_habitos_de_la_gente_altamente_efectiva.pdf
    • http://tonedomopoja.scienceontheweb.net/white_fang_of_the_leaf_sword.pdf
    • https://cdn.sqhk.co/zadorari/jbhiSid/gunimelos.pdf
    • https://cdn-cms.f-static.net/uploads/4470211/normal_603801afbdebb.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/ruzumeb/film_analysis_essay_template.pdf
    • https://a0d2adcf-75bd-42a9-a42a-c23e1c6e9e1a.filesusr.com/ugd/85c99c_b6d4cbdbc16e46d5a64b892fcdf4997f.pdf?index=true
    • https://s3.amazonaws.com/kibavutibeved/tevirebesiwazabedo.pdf
    • https://45f0f727-c607-4398-b3b7-8b42e23b21b2.filesusr.com/ugd/0a84ca_c47e20b71f0b416da7d9acfb9abf6be2.pdf?index=true
    • https://37bdae34-bb2f-403f-997c-54a7c09d9c06.filesusr.com/ugd/dc98cc_1847d2aa60e74178ae3ac08ad78b2ce0.pdf?index=true
    • https://s3.amazonaws.com/dobikasukavu/38355258201.pdf
    • https://s3.amazonaws.com/busutafitufe/28661476797.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f53a.bin
e8a4f56f66d5d8a4b0cc193e3a29b3179541801d31352a099aef1f51ab9a08a4
pdf-font-stream PDF embedded font (sfnt) at offset 0xF53A 5572 bytes
font_01_sfnt_off0001082e.bin
36200a6841d9b2d3f8bfa8d89e8b5998284c82d8c3e1e44f75300495a28f9e73
pdf-font-stream PDF embedded font (sfnt) at offset 0x1082E 10724 bytes